Bump pmdVersion from 7.23.0 to 7.27.0 - #729

This updates the default version of PMD to 7.27.0.
-> https://github.com/pmd/pmd/releases/tag/pmd_releases%2F7.27.0

The rules CheckSkipResult and UselessPureMethodCall have been replaced by the new rule UnusedReturnValue.

• Fixes Warnings about deprecated rules with PMD 7.27.0 #733

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