galaxy-collection datasource not following minimumReleaseAge value

[khung]

How are you running Renovate?

Self-hosted Renovate

If you're self-hosting Renovate, tell us which platform (GitHub, GitLab, etc) and which version of Renovate.

GitHub, v40.11.13

Please tell us more about your question or problem

The documentation says that the galaxy-collection datasource supports release timestamps:
https://docs.renovatebot.com/modules/datasource/galaxy-collection/

The minimumReleaseAge feature says that any datasource supporting release timestamps should work (unless the format is not supported):
https://docs.renovatebot.com/configuration-options/#minimumreleaseage

However, the galaxy-collection datasource does not appear to work with minimumReleaseAge as Renovate picks up the latest version for its PR even if it's below the minimumReleaseAge value.

Minimal reproduction repository is here: https://github.com/khung/galaxy-collection-timestamp-repro

Logs (if relevant)

Logs

DEBUG: packageFiles with updates (repository=local)
       "config": {
         "ansible-galaxy": [
           {
             "deps": [
               {
                 "depType": "galaxy-collection",
                 "currentValue": "2.11.0",
                 "depName": "infra.controller_configuration",
                 "datasource": "galaxy-collection",
                 "updates": [
                   {
                     "bucket": "major",
                     "newVersion": "3.1.2",
                     "newValue": "3.1.2",
                     "downloadUrl": "https://galaxy.ansible.com/api/v3/plugin/ansible/content/published/collections/artifacts/infra-controller_configuration-3.1.2.tar.gz",
                     "newDigest": "363f7b3eaa403028eed56b87aaa9ef0f6b3f3da47b826e956b799d9433470a5b",
                     "newMajor": 3,
                     "newMinor": 1,
                     "newPatch": 2,
                     "updateType": "major",
                     "isBreaking": true,
                     "branchName": "renovate/infra.controller_configuration-3.x"
                   }
                 ],
                 "packageName": "infra.controller_configuration",
                 "versioning": "pep440",
                 "warnings": [],
                 "sourceUrl": "https://github.com/redhat-cop/infra.controller_configuration",
                 "registryUrl": "https://galaxy.ansible.com/api",
                 "currentVersion": "2.11.0",
                 "isSingleVersion": true,
                 "fixedVersion": "2.11.0"
               }
             ],
             "packageFile": "requirements.yml"
           }
         ]
       }

[khung]

It looks like this is still a problem as of Renovate v42.27.1. While I haven't updated the reproduction repository with the latest example, the debug output still does not contain a currentVersionTimestamp field which means that Renovate would not honor the minimumReleaseAge, With the increased focus as of v42 on a secure supply chain, hopefully someone will get the chance to look at this. With v42, the only way I can use the galaxy-collection datasource is to either set minimumReleaseAge=null or minimumReleaseAgeBehavior=timestamp-optional for those dependencies.