Updates the pipeline to validate that packaging a jar works properly

[johnjaylward]

Fixes #796

See also #793, #761 and #760

What problem does this code solve?

Re-adds proper support for Modules on Java 9+. PR #761 was not tested with builds using JDK 8 and the changes only worked when using JDK 9+.

• Validate that the mvn package step completes during the pipeline
• fix issue with package step failing when run on jvm8
• Update the README.md to have correct supported versions
• Adds package artifacts to Action results. see the Actions -> Artifacs section for compiled JARs

A Follow-on PR that enables distribution through GitHub Actions would be worthwhile.

Risks

Low. Changes add new steps to the GitHub actions to ensure that packaging works properly going forward and will only affect the JAR creation

Changes to the API?

None

Will this require a new release?

Yes

Should the documentation be updated?

No, but slight changes were made to the README to:

1. Include workflow status badges
2. Correct the supported Java versions

Does it break the unit tests?

No. New GitHub actions were added to ensure that similar changes will not break release management going forward.

Was any code refactored in this commit?

No.

Review status

APPROVED

Starting 3-day comment window

[johnjaylward]

@stleary can you re-run the last set of jobs, they worked on branch, but not in the PR for some reason

[johnjaylward]

@stleary , this is ready for review now.

[stleary]

Nice work, thanks!