SLES/OpenSUSE variants fail package checks
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### Summary
SLES/OpenSUSE fail package checks due to apparent missing signature file, despite evident attempt to import key signing those packages.
### Steps to reproduce
<!-- How one can reproduce the issue - this is very important -->
Run release pipelines
### What is the current *bug* behavior?
<!-- What actually happens -->
Jobs terminating with:
```
gitlab-ee-18.9.2-ee.0.sles12.x86_64 (gitlab_gitlab-ee): Signature verification failed [4-Signatures public key is not available]
gitlab-ee-18.9.2-ee.0.sles12.x86_64.rpm:
Header V4 RSA/SHA1 Signature, key ID 82dd593d: NOKEY
V4 RSA/SHA1 Signature, key ID 82dd593d: NOKEY
Abort, retry, ignore? [a/r/i] (a): a
Problem occurred during or after installation or removal of packages:
Installation aborted by user
```
### What is the expected *correct* behavior?
<!-- What you should see instead -->
Jobs need to pass (like other RPM-based distro checks)
### Relevant logs
* [SLES-12.5-check (#34831929) · Jobs · GitLab / omnibus-gitlab · GitLab](https://dev.gitlab.org/gitlab/omnibus-gitlab/-/jobs/34831929)
* [OpenSUSE-15.6-check (#34831928) · Jobs · GitLab / omnibus-gitlab · GitLab](https://dev.gitlab.org/gitlab/omnibus-gitlab/-/jobs/34831928)
* [OpenSUSE-15.6-arm64-check (#34831927) · Jobs · GitLab / omnibus-gitlab · GitLab](https://dev.gitlab.org/gitlab/omnibus-gitlab/-/jobs/34831927)
* [OpenSUSE-15.6-check (#34830683) · Jobs · GitLab / omnibus-gitlab · GitLab](https://dev.gitlab.org/gitlab/omnibus-gitlab/-/jobs/34830683)
* [OpenSUSE-15.6-arm64-check (#34830682) · Jobs · GitLab / omnibus-gitlab · GitLab](https://dev.gitlab.org/gitlab/omnibus-gitlab/-/jobs/34830682)
### Details of package version
can be observed with recent releases:
* `18.9.2`
* `18.8.6`
* `18.7.6`
issue