HDDS-10470. Populate Maven dependency cache in separate workflow

[adoroszlai]

What changes were proposed in this pull request?

Create a separate CI workflow to populate the cache for Maven dependencies from scratch. This prevents cache inflation that can happen if existing cache is updated with new dependencies: obsolete dependencies are never removed.

The workflow runs on master and ozone-1.4 branches whenever pom.xml files are changed. It also runs on a schedule to avoid cache miss due to expiry.

Existing workflows are updated to only restore the cache, do not create/update it.

https://issues.apache.org/jira/browse/HDDS-10470

How was this patch tested?

Tested in fork:

• initial commit: https://github.com/adoroszlai/ozone/actions/runs/8170279080/job/22336101638
• no pom change: https://github.com/adoroszlai/ozone/actions/runs/8170585645/job/22337004185
• pom change: https://github.com/adoroszlai/ozone/actions/runs/8170893673/job/22337974520

[smengcl]

Thanks @adoroszlai . lgtm

[adoroszlai]

Thanks @smengcl for the review.