Fix RuboCop offenses in error tracking project setting specs

What does this MR do and why?

This MR fixes some 👮 offenses in error tracking project settings specs.

Note that using verified doubles uncovered two spec bugs.

Screenshots or screen recordings

n/a

How to set up and validate locally

Before

$ REVEAL_RUBOCOP_TODO=1 be rubocop spec/models/error_tracking/project_error_tracking_setting_spec.rb
Inspecting 1 file
C

Offenses:

spec/models/error_tracking/project_error_tracking_setting_spec.rb:51:13: C: RSpec/ContextWording: Start context description with 'when', 'with', or 'without'.
    context 'presence validations' do
            ^^^^^^^^^^^^^^^^^^^^^^
spec/models/error_tracking/project_error_tracking_setting_spec.rb:86:15: C: RSpec/ContextWording: Start context description with 'when', 'with', or 'without'.
      context 'no client key yet' do
              ^^^^^^^^^^^^^^^^^^^
spec/models/error_tracking/project_error_tracking_setting_spec.rb:91:17: C: RSpec/ContextWording: Start context description with 'when', 'with', or 'without'.
        context 'sentry backend' do
                ^^^^^^^^^^^^^^^^
spec/models/error_tracking/project_error_tracking_setting_spec.rb:101:17: C: RSpec/ContextWording: Start context description with 'when', 'with', or 'without'.
        context 'feature disabled' do
                ^^^^^^^^^^^^^^^^^^
spec/models/error_tracking/project_error_tracking_setting_spec.rb:112:15: C: RSpec/ContextWording: Start context description with 'when', 'with', or 'without'.
      context 'client key already exists' do
              ^^^^^^^^^^^^^^^^^^^^^^^^^^^
spec/models/error_tracking/project_error_tracking_setting_spec.rb:172:29: C: RSpec/VerifiedDoubles: Prefer using verifying doubles over normal doubles.
      let(:sentry_client) { spy(:sentry_client) }
                            ^^^^^^^^^^^^^^^^^^^
spec/models/error_tracking/project_error_tracking_setting_spec.rb:178:9: C: RSpec/ExpectInHook: Do not use expect in before hook
        expect(subject).to receive(:sentry_client).and_return(sentry_client)
        ^^^^^^
spec/models/error_tracking/project_error_tracking_setting_spec.rb:198:29: C: RSpec/VerifiedDoubles: Prefer using verifying doubles over normal doubles.
      let(:sentry_client) { spy(:sentry_client) }
                            ^^^^^^^^^^^^^^^^^^^
spec/models/error_tracking/project_error_tracking_setting_spec.rb:217:29: C: RSpec/VerifiedDoubles: Prefer using verifying doubles over normal doubles.
      let(:sentry_client) { spy(:sentry_client) }
                            ^^^^^^^^^^^^^^^^^^^
spec/models/error_tracking/project_error_tracking_setting_spec.rb:224:121: C: Layout/LineLength: Line is too long. [127/120]
          .and_raise(ErrorTracking::SentryClient::MissingKeysError, 'Sentry API response is missing keys. key not found: "id"')
                                                                                                                        ^^^^^^^
spec/models/error_tracking/project_error_tracking_setting_spec.rb:236:29: C: RSpec/VerifiedDoubles: Prefer using verifying doubles over normal doubles.
      let(:sentry_client) { spy(:sentry_client) }
                            ^^^^^^^^^^^^^^^^^^^
spec/models/error_tracking/project_error_tracking_setting_spec.rb:237:24: C: Layout/SpaceInsideBlockBraces: Space missing inside {.
      let(:error_msg) {"Sentry API response is too big. Limit is #{Gitlab::Utils::DeepSize.human_default_max_size}."}
                       ^
spec/models/error_tracking/project_error_tracking_setting_spec.rb:237:117: C: Layout/SpaceInsideBlockBraces: Space missing inside }.
      let(:error_msg) {"Sentry API response is too big. Limit is #{Gitlab::Utils::DeepSize.human_default_max_size}."}
                                                                                                                    ^
spec/models/error_tracking/project_error_tracking_setting_spec.rb:256:29: C: RSpec/VerifiedDoubles: Prefer using verifying doubles over normal doubles.
      let(:sentry_client) { spy(:sentry_client) }
                            ^^^^^^^^^^^^^^^^^^^
spec/models/error_tracking/project_error_tracking_setting_spec.rb:273:27: C: RSpec/VerifiedDoubles: Prefer using verifying doubles over normal doubles.
    let(:sentry_client) { spy(:sentry_client) }
                          ^^^^^^^^^^^^^^^^^^^
spec/models/error_tracking/project_error_tracking_setting_spec.rb:287:27: C: RSpec/VerifiedDoubles: Prefer using verifying doubles over normal doubles.
    let(:sentry_client) { double('sentry_client', issue_details: issue) }
                          ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
spec/models/error_tracking/project_error_tracking_setting_spec.rb:299:9: C: RSpec/ExpectInHook: Do not use expect in before hook
        expect(subject).to receive(:sentry_client).and_return(sentry_client)
        ^^^^^^
spec/models/error_tracking/project_error_tracking_setting_spec.rb:317:24: C: RSpec/VerifiedDoubles: Prefer using verifying doubles over normal doubles.
        let(:commit) { double('commit', id: commit_id) }
                       ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
spec/models/error_tracking/project_error_tracking_setting_spec.rb:318:28: C: RSpec/VerifiedDoubles: Prefer using verifying doubles over normal doubles.
        let(:repository) { double('repository', commit: commit) }
                           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
spec/models/error_tracking/project_error_tracking_setting_spec.rb:321:11: C: RSpec/ExpectInHook: Do not use expect in before hook
          expect(project).to receive(:repository).and_return(repository)
          ^^^^^^
spec/models/error_tracking/project_error_tracking_setting_spec.rb:325:121: C: Layout/LineLength: Line is too long. [130/120]
        it { expect(result[:issue].gitlab_commit_path).to eq("/#{project.namespace.path}/#{project.path}/-/commit/#{commit_id}") }
                                                                                                                        ^^^^^^^^^^
spec/models/error_tracking/project_error_tracking_setting_spec.rb:344:27: C: RSpec/VerifiedDoubles: Prefer using verifying doubles over normal doubles.
    let(:sentry_client) { spy(:sentry_client) }
                          ^^^^^^^^^^^^^^^^^^^
spec/models/error_tracking/project_error_tracking_setting_spec.rb:346:13: C: RSpec/ContextWording: Start context description with 'when', 'with', or 'without'.
    context 'successful call to sentry' do
            ^^^^^^^^^^^^^^^^^^^^^^^^^^^
spec/models/error_tracking/project_error_tracking_setting_spec.rb:357:13: C: RSpec/ContextWording: Start context description with 'when', 'with', or 'without'.
    context 'sentry raises an error' do
            ^^^^^^^^^^^^^^^^^^^^^^^^
spec/models/error_tracking/project_error_tracking_setting_spec.rb:369:11: C: RSpec/ContextWording: Start context description with 'when', 'with', or 'without'.
  context 'slugs' do
          ^^^^^^^
spec/models/error_tracking/project_error_tracking_setting_spec.rb:396:11: C: RSpec/ContextWording: Start context description with 'when', 'with', or 'without'.
  context 'names from api_url' do
          ^^^^^^^^^^^^^^^^^^^^
spec/models/error_tracking/project_error_tracking_setting_spec.rb:398:15: C: RSpec/ContextWording: Start context description with 'when', 'with', or 'without'.
      context 'name is present in DB' do
              ^^^^^^^^^^^^^^^^^^^^^^^
spec/models/error_tracking/project_error_tracking_setting_spec.rb:407:15: C: RSpec/ContextWording: Start context description with 'when', 'with', or 'without'.
      context 'name is null in DB' do
              ^^^^^^^^^^^^^^^^^^^^

1 file inspected, 28 offenses detected, 4 offenses auto-correctable

After

$ REVEAL_RUBOCOP_TODO=1 be rubocop spec/models/error_tracking/project_error_tracking_setting_spec.rb
Inspecting 1 file
.

1 file inspected, no offenses detected

MR acceptance checklist

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