Update current stack version to 9.0.8

[nastasha-solomon]

⚠️ DO NOT MERGE UNTIL RELEASE DATE ⚠️

Bumps the docs version to 9.0.8

[florent-leborgne]

I think this PR should be closed, we're not supposed to update this for patch releases of previous minors

[nastasha-solomon]

@florent-leborgne in this context, would a previous minor be any unreleased version that's lower than 9.1.5? Also, if this PR ends up being closed because it's not needed, should I notify the Dev release manager, or would it be sufficient to leave a note about this PR in the 9.0.8 docs release issue?

[florent-leborgne]

This PR #1974 updates the same thing as this one. We're only keeping track of the latest patch of the latest released minor version (9.1.5 then 9.1.6, etc. until 9.2 releases, then we'll track 9.2.0, 9.2.1, 9.2.3, etc. until 9.3 releases, and so on)

For all other patch releases, I think all we need to do is to confirm that we've published the release notes on release day.

[nastasha-solomon]

Closing as per Florent's comments.