Move docs deployment to CircleCI

[THenry14]

We should move docs deployments to circleCI config. There seemed to be some issues when deploying to already existing branch using gh-pages, that may need to be investigated a bit closer.

Following step can be used for deployment in circleci https://github.com/software-mansion/protostar/pull/1919/commits/e465b2dabb7c2b0d9a976042d83358d7ba2bd1c8

Steps:

• fork repo
• add changes from attached commit
• check for errors in circleci
• make sure no files on branch gh-pages are overwritten when running the job multiple times, and .nojekyll file exists (if not, add it in step)
• remove gh action deploy_docs.yml file

DoD:

• circleci now automatically releases docs when new protostar version is released