fix: force runasuser for reduce-snapshot

[scoheb]

Describe your changes

• This is a workaround for a problem observed on a particular cluster where the use-trusted-artifacts step runs with root user causing a file or folder to not be readable in later steps. There might be solution coming related to the security context constraints on the cluster, but setting this explicitly here should probably be harmless either way.

Checklist before requesting a review

• I have marked as draft or added do not merge label if there's a dependency PR
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• My commit message includes Signed-off-by: My name <email>
• I read CONTRIBUTING.MD and commit formatting
• I have run the README.md generator script in .github/scripts/readme_generator.sh and verified the results using .github/scripts/check_readme.sh

[scoheb]

before:

Single Component mode is true and Snapshot type is component
COMPONENT_COUNT: 1
tee: /var/workdir/release/2672fdf6-a311-48ff-9f7c-8ac2983e92a8/snapshot_spec.json: Permission denied
{
  "application": "rhel-10",
  "artifacts": {},
  "components": [
    {
      "containerImage": "quay.io/redhat-user-workloads/rhel-sst-cs-databases-tenant/rhel-10-gdbm@sha256:cdf5f24a9608b718a8274e849fd336410076144d409f408b05324976f632044d",
      "name": "rhel-10-gdbm",
      "source": {
        "git": {
          "revision": "318c1c2dabb2365a5f4fe23d37197d211985805a",
          "url": "https://gitlab.com/redhat/centos-stream/rpms/gdbm"
        }
      }
    }
  ]
}

after:

Single Component mode? true
SNAPSHOT_CREATION_TYPE: component
SNAPSHOT_CREATION_COMPONENT: rhel-10-gdbm
Single Component mode is true and Snapshot type is component
COMPONENT_COUNT: 1
{
  "application": "rhel-10",
  "artifacts": {},
  "components": [
    {
      "containerImage": "quay.io/redhat-user-workloads/rhel-sst-cs-databases-tenant/rhel-10-gdbm@sha256:cdf5f24a9608b718a8274e849fd336410076144d409f408b05324976f632044d",
      "name": "rhel-10-gdbm",
      "source": {
        "git": {
          "revision": "318c1c2dabb2365a5f4fe23d37197d211985805a",
          "url": "https://gitlab.com/redhat/centos-stream/rpms/gdbm"
        }
      }
    }
  ]
}

[scoheb]

/retest

[scoheb]

/retest

[scoheb]

re-running 2 failed tests

[scoheb]

/retest

[scoheb]

/retest

[scoheb]

/retest

[theflockers]

/retest

[xiangge]

Are we ok to merge this? It's blocking the pipeline.

[jinqi7]

/retest

[seanconroy2021]

LGTM

[openshift-ci]

New changes are detected. LGTM label has been removed.