Convert `$apollo` mocks in tests to using mocked Apollo Client
Our recommended strategy for testing Vue components with Apollo operations now is mocking Apollo Client in tests. However, there are a few specs where we still mock `$apollo` with `mocks` property when mounting a component. These tests should be refactored to using mocked Apollo client. This would also allow us to remove the unnecessary `createLocalVue` calls from tests
### List of tests with `$apollo` mock
* [ ] ee/spec/frontend/analytics/group_ci_cd_analytics/components/shared_runner_usage_spec.js
* [ ] ee/spec/frontend/iterations/components/iteration_breadcumb_spec.js
* [ ] ee/spec/frontend/iterations/components/iteration_report_without_vue_router_spec.js
* [ ] ee/spec/frontend/on_demand_scans_form/components/on_demand_scans_form_spec.js
* [ ] ee/spec/frontend/on_demand_scans_form/components/profile_selector/dast_profiles_selector_spec.js
* [ ] ee/spec/frontend/oncall_schedule/add_edit_schedule_modal_spec.js
* [ ] ee/spec/frontend/oncall_schedule/delete_schedule_modal_spec.js
* [ ] ee/spec/frontend/oncall_schedule/rotations/components/add_edit_rotation_modal_spec.js
* [ ] ee/spec/frontend/oncall_schedule/rotations/components/delete_rotation_modal_spec.js
* [ ] ee/spec/frontend/requirements/components/requirements_root_spec.js
* [ ] ee/spec/frontend/security_dashboard/components/group/group_vulnerabilities_spec.js
* [ ] ee/spec/frontend/security_dashboard/components/instance/instance_vulnerabilities_spec.js
* [ ] ee/spec/frontend/security_dashboard/components/project/project_vulnerabilities_spec.js
* [ ] ee/spec/frontend/security_dashboard/components/shared/vulnerability_count_list_spec.js
* [ ] ee/spec/frontend/threat_monitoring/components/alerts/alert_drawer_spec.js
* [ ] ee/spec/frontend/threat_monitoring/components/alerts/alerts_list_spec.js
* [ ] ee/spec/frontend/trials/components/trial_create_lead_form_spec.js
* [ ] spec/frontend/clusters/agents/components/show_spec.js
* [ ] spec/frontend/clusters_list/components/agents_spec.js
* [x] spec/frontend/packages_and_registries/container_registry/explorer/components/details_page/details_header_spec.js
* [x] spec/frontend/packages_and_registries/settings/project/settings/components/settings_form_spec.js
* [ ] spec/frontend/pipeline_editor/components/file-nav/branch_switcher_spec.js
* [ ] spec/frontend/pipeline_editor/pipeline_editor_app_spec.js
* [ ] spec/frontend/pipelines/notification/deprecated_type_keyword_notification_spec.js
* [ ] spec/frontend/runner/admin_runners/admin_runners_app_spec.js
* [ ] spec/frontend/runner/components/cells/runner_actions_cell_spec.js
* [ ] spec/frontend/runner/components/registration/registration_token_spec.js
* [ ] spec/frontend/runner/components/runner_update_form_spec.js
epic