Automatically build and publish release artifacts

[benknoll-umn]

With every release a number of new MTAP artifacts are published:

• The Python wheel and source dist to PyPI
• The Java pom and jars to Sonatype Nexus OSSRH
• The Go gateway binaries to the GitHub release

Currently all of these require some level of manual interaction, this complicates the release process and uses developer time. It also creates a developer information burden where the release process needs to be documented.

This process should be automated via GitHub Actions.