Added github actions for release and deploy

release:

• triggered by push or merged PR on main
• Creates a new release draft with incremented version number
  deploy:
• triggered by release
• Builds image
• pushes to Dockerhub
• Creates new revision on azure (does not redirect traffic yet)

Workflow for deployment:
-> push or merge pr on main
-> Go to releases and click publish release
-> go to azure portal. Check if deployment was successful and then redirect traffic