Follow-up Docker image build fix. Fix directory structure for latest-dist digests

[tdonohue]

References

• Fixes another bug initially in Setup the Docker GH Action for Matrix Building #2644 which I overlooked in Fix bug in Docker image build process which caused tags to have improper manifests in DockerHub #2648

Description

This is a minor fix to the directory structure of where latest-dist digests are stored. This fix is necessary so that the new matrix process works properly... without it, the latest-dist digests cannot be found, resulting in issues in DockerHub.

Instructions for Reviewers

• Will be merged immediately as this is only possible to test after the PR is merged. I've triple-checked my work though, so I feel this should finally get these parallel Docker image builds working properly

Once this is succeeding on main, all these changes will be backported to dspace-7_x.

[tdonohue]

The code changes in the docker.yml file made in this PR are only triggered when a PR is merged. Therefore, I'm merging this immediately as it's (unfortunately) the only way to test these changes fix the bug.

[tdonohue]

Ported to dspace-7_x in #2655