Network/Graph view does not show tags which are not part of a branch

Summary

In our /-/network/ views, the repo graph does not include tags that have been pushed directly

Steps to reproduce

See internal customer case ZD 356259 for detailed steps, or the activity in the example project.

Example Project

In gitlab-silver/katrinleinweber-kl-tests/zd-356259-push-tag, compare /-/commits/t1/ & /network/t1 views.

What is the current bug behavior?

The t1 tag is not shown. Setting severity3 because the workaround is to run git log --oneline --graph …tag…name… offline.

What is the expected correct behavior?

It should be shown, and maybe highlighted as being outside of a branch, like GitHub does:

This commit does not belong to any branch on this repository, and may belong to a fork outside of the repository.

Relevant logs and/or screenshots

See example project links above.

Output of checks

This bug happens on GitLab.com>

Possible fixes