Fixes #28644 - Repo Mapper prunes unused subs

[parthaa]

Prior to this commit any action that did something like
PUT /katello/api/v2/products/572/repository_sets/7441/enable/
-d '{"releasever":"8", "basearch":"x86_64"}'
would set the arch for a repository using the basearch value even if
basearch is an invalid/unused url substitution. This caused weird bugs
with repo enablement unacknowleged etc

This commit clears out unused subtitutions before the url path is mapped
via repo mapper. This sets the correct value for the arch in the
repository object

[theforeman-bot]

Issues: #28644

[parthaa]

• Import a manifest with RHEL 8
• Go to Content-> Redhat Repositories -> content_label=rhel-8-for-x86_64-appstream-rpms
• Open up webconsole
• Expand the appstream repository set and enable the 8.0 repo
• Go to the webconsole -> network and identify the product id and repository set id from the enable call. Might look something like
  http://example.com:3000/katello/api/v2/products/572/repository_sets/7441/enable/ with a payload that looks like '{"releasever":"8"}
• Now disable the enabled repo
• Checkout Master
• Go to the command line and run

$ curl -k -u admin:changeme -H 'Content-Type: application/json' -X PUT  http://example.com:3000/katello/api/v2/products/572/repository_sets/7441/enable/ -d '{"releasever":"8", "basearch":"x86_64"}'
$ yum install jq -y #unless you want to use something else
$  curl -k -u admin:changeme http://example.com:3000/katello/api/products/572/repository_sets/7441/available_repositories?organization_id=4 | jq .

{
...
  "results": [
    {
      "substitutions": {
        "releasever": "8"
      },
      "path": "/content/dist/rhel8/8/x86_64/appstream/os",
      "repo_name": "Red Hat Enterprise Linux 8 for x86_64 - AppStream RPMs 8",
      "pulp_id": "d76590eb-d356-4605-bf01-24cd6b15ba70",
      "name": "Red Hat Enterprise Linux 8 for x86_64 - AppStream (RPMs)",
      "enabled": false,
      "promoted": false,
      "repository_id": 46
    },
 ...
  ]
}

• Note even though you enabled rhel 8 you see that enabled is marked false
• Go to the RH Repos page again. You should notice an Enabled repo there
• Search for content_label=rhel-8-for-x86_64-appstream-rpms and expand that repository set again
• Notice that 8.0 is still marked 'enableable'
• Disable the enabled repo
• Checkout this PR
• Go to the command line and run

$ curl -k -u admin:changeme -H 'Content-Type: application/json' -X PUT  http://example.com:3000/katello/api/v2/products/572/repository_sets/7441/enable/ -d '{"releasever":"8", "basearch":"x86_64"}'
$ yum install jq -y #unless you want to use something else
$  curl -k -u admin:changeme http://example.com:3000/katello/api/products/572/repository_sets/7441/available_repositories?organization_id=4 | jq .

{
...
  "results": [
    {
      "substitutions": {
        "releasever": "8"
      },
      "path": "/content/dist/rhel8/8/x86_64/appstream/os",
      "repo_name": "Red Hat Enterprise Linux 8 for x86_64 - AppStream RPMs 8",
      "pulp_id": "d76590eb-d356-4605-bf01-24cd6b15ba70",
      "name": "Red Hat Enterprise Linux 8 for x86_64 - AppStream (RPMs)",
      "enabled": true,
      "promoted": false,
      "repository_id": 46
    },
 ...
  ]
}

• Note even though you enabled is marked true for rhel 8

• Go to the RH Repos page again. You should notice an Enabled repo there

• Search for content_label=rhel-8-for-x86_64-appstream-rpms and expand that repository set again

• You should not see 8.0 in the repository set.

[jturel]

Works as advertised and I think it addressed the problem. ACK

[chris1984]

Ack, works as described.