If you set the IMAGE_NAME variable, then the base image will use that name,
but the api image would previously use a hardcoded `deepset/haystack` image name.
* setup base images
* add cpu flavor
* use the same Dockerfile for cpu and gpu
* better naming, add docs
* add docker workflow
* add missing image input
* change cwd for bake
* also push api images
* try conditional tagging for releases
* revert testing code
* update docker readme
* document variable override
* use Python 3.10
* allow empty HAYSTACK_EXTRAS
* Apply suggestions from code review
Co-authored-by: Sara Zan <sara.zanzottera@deepset.ai>
* remove repo description step, can't make it work so far
* add docs to the last step as it's tricky
* manage tags for the newest images
* tests are passing, checking in the last bit
Co-authored-by: Sara Zan <sara.zanzottera@deepset.ai>
