Bump ruby v2.7.7

Bump to ruby v2.7.7 from v2.7.5

This dependency update implements major security fixes of ruby:

• https://www.ruby-lang.org/en/news/2022/04/12/ruby-2-7-6-released/
• https://www.ruby-lang.org/en/news/2022/04/12/ruby-2-7-7-released/

The fix was tested on a local rdms development instance (laptop). The containers are built, up and running RDMS normally.