github actions workflow to build docker from dispatch

[kelly-sovacool]

• in another repo (e.g. MOSuite, SCOT), have a gha workflow that triggers a workflow in this repo to run via workflow_dispatch trigger
• get version tag from dispatch payload
• copy dockerfile to Dockerfile.{version_tag}
• build and push

This way, we can move Dockerfiles defined in MOSuite & SCOT to this repo