DAS-1937 - Add GitHub workflows for unit tests and Docker image publication.

[owenlittlejohns]

Description

This PR adds CI/CD to the repository such that it will:

• Run the unit test suite for all PRs against the main branch.
• For changes merged to main, with changes to docker/service_version.txt, the tests will run, then the HOSS service Docker image will be built and published, the commit will be tagged and a GitHub release will be created.

Jira Issue ID

DAS-1937

Local Test Steps

I've worked through the teething issues in a fork of the repo:

• Here's a successful run of the tests on a PR
• Here's a successful run of the publication workflow
• Here's the resulting ghcr.io hosted image
• Here's the resulting release
• This is the published git tag

Note - I will delete this fork after this PR is merged.

PR Acceptance Checklist

• Jira ticket acceptance criteria met. (Minus the actual publication, which will happen after this PR is merged)
• CHANGELOG.md updated to include high level summary of PR changes.
• VERSION updated if publishing a release.
• Tests added/updated and passing.
• Documentation updated (if needed).

[owenlittlejohns]

The tests running in this PR are also a good verification of the new run_tests_on_pull_requests.yml and run_tests.yml workflows. 🎉

[owenlittlejohns]

The packages permission is new in comparison to HGA and NetCDF-to-Zarr, however, I could not get my fork to create the package without it. I got guidance from StackOverflow and also the GitHub documentation.

[owenlittlejohns]

@flamingbear - sorry to have to tag you again. (I wonder if you aren't added on this repository because even though it starts with "harmony", it was made after you made your NAMS request?)

[flamingbear]

Excellent! I was able to fork the repo and run the actions to test a PR to main running the tests and pushing an image to ghcr.io. Didn't see any typos either.