Optimize class path cache files

[EduardKrieger]

Adresses/Fixes #1476. Initial version to cache the dependencies more efficient and less error prone.

Implements

• generatePomFileHash reworked also takes m2 repo into account.
• validation of the existing cache, checking if file exists and is in the correct repository
• added unit tests for both functionalities
• Integration test with the new cache functions

@devonfw/cobigen