Bump default ruby version to 3.2.9

What does this MR do and why?

All patch versions have been bumped to their latest in ci images project. This bumps the patch version for default ruby version to latest one.

This also fixes not having the image for ubi gem caching jobs because that image was added after version was bumped so it doesn't exist with older ruby version: https://gitlab.com/gitlab-org/gitlab/-/jobs/11051080458

References

Improve CI caching setup in gitlab-org/gitlab (gitlab-org/quality/analytics&21 - closed)

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