Re-add UID/GID stability checks on feature/buster

As the base system changes to much with buster - the underlying system groups also changes, so we can’t keep the GIDs from further versions.
At the moment we just remove the script, t get the iso being build.

Feature Branch: bugfix/15690-stop-installing-all-priority-standard-packages

Related issues

Related to #16322 (closed)
Blocked by #15690 (closed)

Original created by @Hefee on 15854 (Redmine)

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