Upgrade brakeman analyzer to 5.0 and start scanning all ruby files

Brakeman 5.0 has been released and we should update our brakeman analyzer. Among other things, this update allows for the scanning of almost all Ruby files in a project. We should take advantage of this to increase the number of Ruby projects we scan.

• Update the analyzer to Brakeman 5.0, utilizing the --force to scan all Ruby projects, and update to match on Ruby files - MR
• Add a test project demonstrating found issues in a non-Rails project - ruby-generic
• Update brakeman analyzer to QA ruby-generic project - MR
• Update our SAST vendored template to match on Ruby files (instead of config/routes.rb) - MR
• Update documentation to indicate we now analyze Ruby projects instead of just Rails projects - MR closed, see note
• Update documentation to indicate we now analyze Ruby projects as well as Ruby on Rails projects - MR

Release notes

Draft release post notes