rabbit_vhost:set_tags/2 avoids notifying if tags are unchanged (backport #7280)

[mergify]

This is an automatic backport of pull request #7280 done by Mergify.
Cherry-pick of 12ec3a5 has failed:

On branch mergify/bp/v3.11.x/pr-7280
Your branch is up to date with 'origin/v3.11.x'.

You are currently cherry-picking commit 12ec3a55ff.
  (fix conflicts and run "git cherry-pick --continue")
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Changes to be committed:
	modified:   deps/rabbit/BUILD.bazel
	new file:   deps/rabbit/test/test_rabbit_event_handler.erl
	modified:   deps/rabbit/test/vhost_SUITE.erl

Unmerged paths:
  (use "git add/rm <file>..." as appropriate to mark resolution)
	deleted by us:   deps/rabbit/src/rabbit_db_vhost.erl
	both modified:   deps/rabbit/src/rabbit_vhost.erl

To fix up this pull request, you can check it out locally. See documentation: https://docs.github.com/en/github/collaborating-with-pull-requests/reviewing-changes-in-pull-requests/checking-out-pull-requests-locally

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[HoloRin]

@michaelklishin maybe this should not actually be backported, unless the rabbit_db_* PRs will be backported as well?

[HoloRin]

On second though, I'll fixup the merge

[michaelklishin]

@pjk25 I have asked for rabbit_db_* to be backported partially to make backports of other PRs easier.