Update E2E tests using the blob text viewer

What does this MR do?

Test updates needed to account for !65451 (merged)

This is blocked by some tests that fail because a bug in the UI when the refactor_blob_viewer feature flag is enabled:

• #335378 (closed) - codeowners tests fail

• #336052 (closed) - fails qa/specs/features/ee/browser_ui/1_manage/user/minimal_access_user_spec.rb and qa/specs/features/browser_ui/1_manage/user/user_access_termination_spec.rb | Fixed by !71537 (merged)

• #336479 (closed) - fails qa/specs/features/browser_ui/3_create/repository/branch_with_unusual_name_spec.rb | Fixed by !66156 (merged)

• The file lock tests fail but they're being fixed in !67850 (merged)

• The commit that enables the refactor_blob_viewer feature flag must be removed before this MR is merged.

MR acceptance checklist

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