Bump Mailroom container from v0.0.19 to v0.0.23

What does this MR do?

This backports the version used to the 6-11-stable branch . This is the version shipped with Omnibus already.

Main changes:

• Support alternative Azure deployments for Microsoft Graph
• Drop io-wait dependency requirement as io-wait 0.2.1 supports Ruby < 3
• Allow OAuth2 v2 gem

Testing

Did a smoke test with Microsoft Graph, and it appears to work.

Note the OAuth2 v2 gem was bumped as a result:

irb(main):001:0> require 'oauth2'
=> true
irb(main):002:0> OAuth2::Version::VERSION
=> "2.0.9"

Related issues

Relates to #4686 (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
• When ready for review, MR is labeled "~workflow::ready for review" per the Distribution MR workflow

Expected (please provide an explanation if not completing)

• Test plan indicating conditions for success has been posted and passes
• Documentation created/updated
• Tests added
• Integration tests added to GitLab QA
• Equivalent MR/issue for omnibus-gitlab opened
• Validate potential values for new configuration settings. Formats such as integer 10, duration 10s, URI scheme://user:passwd@host:port may require quotation or other special handling when rendered in a template and written to a configuration file.