[Docs] Blog post on our migration to Github Actions for CI

[roleyfoley]

Documentation Topic

Show the changes we have made to our build/test processes by discussing our CI approach and our migration

Description

Outline how we used to run on Jenkins
Outline the running hamlet container to build hamlet container issue
Outline how it works with engines
Show the CI process and testing performance updates

Audience

potential hamlet users

Checklist

The following locations should be reviewed for documentation

• https://docs.hamlet.io/ (everyone)
• https://help.hamlet.io (everyone)
• Applicable repository README.md (developers of Hamlet Deploy only)
• Architectural Decision Log (developers of Hamlet Deploy only)