Show sub-nav under Merge Requests when issue tracker is non-default

What does this MR do?

When project has 3rd-party Issue tracker integration, clicking on Issues tab will directly take user to issue tracker page. Starting %9.0 we changed navigation order for Projects (see #26348 (closed)), where we removed sub-nav items from Merge Requests tab and showed them under Issues tab. In this case, user will never see sub-nav since page is redirected to 3rd-party issue tracker.

This MR restores sub-nav under Merge Requests when project has non-default Issue tracker (eg; JIRA, Bugzilla) integrated with the project. See #30779 (closed).

Does this MR meet the acceptance criteria?

• Changelog entry added, if necessary
• [ ] Documentation created/updated
• [ ] API support added
• Tests
  • [ ] Added for this feature/bug
  • All builds are passing
• Conform by the merge request performance guides
• Conform by the style guides
• Branch has no merge conflicts with master (if it does - rebase it please)
• Squashed related commits together

What are the relevant issue numbers?

Closes #30779 (closed)

marked the task All builds are passing as completed

marked the task Conform by the merge request performance guides as completed

marked the task Conform by the style guides as completed

marked the task Branch has no merge conflicts with master (if it does - rebase it please) as completed

marked the task Squashed related commits together as completed

added 1 commit

• 87407912 - [ci skip] Add changelog entry

Compare with previous version

marked the checklist item Changelog entry added, if necessary as completed

@alfredo1 can you please review and merge?

assigned to @alfredo1

resolved all discussions

Tested and works great. Thanks @kushalpandya LGTM

approved this merge request

@kushalpandya can you not skip the CI tests Can you push again your last commit without the [ci skip] tag so I can merge after tests has passed?

assigned to @kushalpandya

@alfredo1 the first pipeline with actual changes passed so I thought to skip running whole thing again just for changelog entry. No problem though, I'll update with new commit.

added 1 commit

• 7c612b3c - Updated changelog message

Compare with previous version

approved this merge request

enabled an automatic merge when the pipeline for 7c612b3c succeeds

thanks @kushalpandya I didn't knew if the last pipeline passed.

@alfredo1 this is in fact an interesting UX case, we can may be show if previous pipeline passed in MR widget no matter what current pipeline status is.

Yeah I asked about that in development. Looks like we miss that functionality

merged

mentioned in commit 9daf4f64

@alfredo1 @kushalpandya this is Pick into Stable but has no milestone. Where should this go? 9.1, 9.0, both, none of them?

@jameslopez Both actually, since nav change was introduced in %9.0, so chances are this regression was always there since then, which milestone should we add then?

ah! In that case 9.1 first. /cc @godfat @felipe_artur @twk3

changed milestone to %9.1

mentioned in issue #31059 (closed)

Picked into 9-1-stable, will go into 9.1.0-rc6

changed milestone to %9.0

mentioned in commit 57d40668

mentioned in commit 461068f8

Picked into 9-0-stable, will go into 9.0.6