Revert "Merge branch '5688-opensuse-15.1-deprecation' into 'master'"

What does this MR do?

Due to the problem described in #5735 (closed), we can't provide packages for openSUSE Leap 15.2 in 13.5. So we can't deprecate 15.1 yet, since users have no alternative. Hence, reverting !4610 (merged)

Related issues

#5735 (closed)

Checklist

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