Migrate CI from CircleCI to Github Actions - Editor-API

[sra405]

RPF are moving away from CircleCI, so we need to migrate Editor-API to Github Acctions.

As a CE Engineer
I want to be able to do CI through Github Actions and not CircleCI
So that I have a better Developer Experience and save RPF money

Notes 🗒️

• Patrick has already done some work Patrick's work

ACs ✅

• Editor API has no requirements of Circle CI
• Editor API is fully built using GitHub Actions
• All CE Engineers have had a knowledge-sharing session on pipelines
• All CE Engineers have an understanding of show to run CI process.

[ce-rpf]

Appears to have been started here: #164

[patch0]

See also clubs-api for a Docker-container-build/test/publish, or codeclub for a more traditional install-gems-locally-and-test

[adrian-rpf]

https://docs.google.com/spreadsheets/d/1LsKhpIxUQgsSRRM_mi-GeTHbabn-2M58xDoYcQp_ogc/edit?gid=0#gid=0