Generalize references to the release date in the docs

What does this MR do?

This makes similar changes as we did in the handbook in Generalizing references to `22nd` and linking t... (gitlab-com/www-gitlab-com!127846 - merged), as part of gitlab-com&2184.

We don't need to specifically say we release on the 22nd of the month, we can just say we release every month. Starting with November 2023, we'll release on the Third Thursday of the month instead of the 22nd, so this change helps with that transition.

Related issues

Resolves #418900 (closed)

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