Add files required to consistently build Alpine APKs for January Release

[steelhead31]

Add the usual APKs so that the previous method of building the APK files works, also pin the alpine builds to docker latest.

[github-actions]

A block has been put on this Pull Request as this repository is temporarily under a code freeze due to an ongoing release cycle.

If this pull request needs to be merged during the release cycle then please comment /merge and a PMC member will be able to remove the block.

If the code freeze is over you can remove this block by commenting /thaw.

[smlambert]

/merge

[github-actions]

Approval to merge during the lockdown cycle

Please can two Adoptium PMC members comment /approve?

[smlambert]

/approve

[sxa]

As long as the removal of the / in:

def fullURL = "${baseURL}/${binaryRepo}"

is safe than I'm good with this - as far as I can tell there's nothing otherwise risky here

[sxa]

/approve

Thank you @smlambert and @sxa for your approvals, this pull request is now approved to merge during release.