Bump Ruby version to 3.0.5

What does this MR do?

CNG counterpart of gitlab-org/omnibus-gitlab!6736 (merged)

1. Enable iteratively switching deployments to newer version of Ruby
2. Switch all builds to Ruby 3

Related issues

gitlab-org/omnibus-gitlab#6287 (closed)

Checklist

See Definition of done.

For anything in this list which will not be completed, please provide a reason in the MR discussion

Required

• Merge Request Title, and Description are up to date, accurate, and descriptive
• MR targeting the appropriate branch
• MR has a green pipeline on GitLab.com

Expected (please provide an explanation if not completing)

• Test plan indicating conditions for success has been posted and passes
• Documentation created/updated
• Integration tests added to GitLab QA
• The impact any change in container size has should be evaluated