Fix Artifact release to also publish HCD 1.2 Agent

[emerkle826]

• Combine release jobs into single workflow file
• Refactor Integration tests into its own submodule. Refactor Dockerfiles so building an image does not have to rebuild the artifacts within the Docker image build process
• Update Docker release to use release version artifacts
  Fixes Fix Artifact release to also publish HCD 1.2 Agent #590
  Fixes Optimize Docker image releases #586

[emerkle826]

@burmanm I would appreciate a review of this if you have some time.

[burmanm]

I assume the main benefit is faster CI when we don't need to compile mgmt-api for every version all the time?

[emerkle826]

I assume the main benefit is faster CI when we don't need to compile mgmt-api for every version all the time?

Yes, but really it's an attempt to get more reliable Docker image builds. Lately, when we do a release, I've had to re-run some of the Docker builds multiple times because each of the 118 images will also run a Maven build. Eventually a handful of them will fail because of some issue pulling artifacts from our Maven Artifactory.

With these changes, we build the branch/tag once and cache the build artifacts so the follow-on jobs can just restore and then build images by just copying the artifacts in.

Another approach I considered was going back to a "base" image that just builds the artifacts, and then pushing that image to a local repo that all the real image builds could simply pull from. I could still do that, if you think that would be a better approach.

[burmanm]

I could still do that, if you think that would be a better approach.

No, this is fine, we get the built files in the action artifacts, easier to debug if something went wrong.