* Adding simple setup.py to ui/ and rest_api and remove respective extras from main setup.cfg
* Make 'pip install rest_api/' fetch the local Haystack instead of downloading from pypi
* Add some comments to the new setup.py files and fix the Dockerfiles
* Add version info to 'farm-haystack-ui'
* Fix the OpenAPI Specs workflow
* Install rest_api and ui properly on the CI too
* Make the workflow see changes on every setup file
* Fix workflow cache keys
* Add license to rest_api and ui
