Move spinach group milestones test to RSpec
What does this MR do?
Replace spinach test with RSpec analog
Why was this MR needed?
This is a part of https://gitlab.com/gitlab-org/gitlab-ce/issues/23036
- [-] Changelog entry added, if necessary
- [-] Documentation created/updated
- [-] API support added
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Tests added for this feature/bug - Review
- [-] Has been reviewed by UX
- [-] Has been reviewed by Frontend
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Has been reviewed by Backend -
Has been reviewed by Database
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Conform by the merge request performance guides -
Conform by the style guides -
Squashed related commits together - [-] Internationalization required/considered
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End-to-end tests pass ( package-qa
manual pipeline job)