Feature Request: Create build pipeline to build and publish MMS container image

[bencourliss]

Currently the MMS container image is built and published by an IBM-internal Jenkins pipeline that make it difficult for open-source developers to see how its done. In addition, this is only done on a nightly basis with no way for non-IBM employees to trigger it.

We need to have a pipeline that builds and publishes the MMS container image into Dockerhub. This pipeline should ideally take the form of Github Actions and operate off of pull requests. The pipeline should publish the testing tag to Dockerhub upon completion.