rabbitmq-diagnostics status: adjust the (date-based) support status field to match the current community support policy (backport #11386) (backport #11387)

[mergify]

As of [1], this field has become irrelevant or even misleading.

1. https://www.rabbitmq.com/blog/2024/05/31/new-community-support-policy

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This is an automatic backport of pull request #11386 done by [Mergify](https://mergify.com).

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This is an automatic backport of pull request #11387 done by [Mergify](https://mergify.com).

[mergify]

Cherry-pick of 53c67ce has failed:

On branch mergify/bp/v3.12.x/pr-11387
Your branch is up to date with 'origin/v3.12.x'.

You are currently cherry-picking commit 53c67ce45b.
  (fix conflicts and run "git cherry-pick --continue")
  (use "git cherry-pick --skip" to skip this patch)
  (use "git cherry-pick --abort" to cancel the cherry-pick operation)

Changes to be committed:
	modified:   deps/rabbitmq_cli/lib/rabbitmq/cli/ctl/commands/status_command.ex

Unmerged paths:
  (use "git add <file>..." to mark resolution)
	both modified:   deps/rabbit/src/rabbit.erl
	both modified:   deps/rabbit/src/rabbit_release_series.erl

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