[MSHADE-326] Remove bad workspace cache which caused problems in maven-shade-plugin

[nielsbasjes]

This is a proposed merge request that came from the discussion of
apache/maven-shade-plugin#26
https://issues.apache.org/jira/browse/MSHADE-326

Essentially the discussion (with @michael-o @rfscholte) came to the point where it seemed that the rootcause of the problem in the maven-shade-plugin was really a problem in maven itself where it does not reload the changes in the project (after shade modified it) thus causing incorrect data to be read in the rest of a multi-module project.

This simply removes this "skip cache refresh" code (that was originally annotated as a hack!)

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[michael-o]

We will also need to reconsider MNG-6638 becaue we cannot drop this cache with fixing MNG-6638. We obviously need to check whether this is stale..

[nielsbasjes]

@michael-o How can MNG-6638 be tested? Looking at the changes for this I only see some additional code in MavenMetadataSource.java that retrieves some existing data, no tests (and the removal of the hack comment).

[nielsbasjes]

The only test that failed in CI is MavenITmng5895CIFriendlyUsageWithPropertyTest and it only fails on Windows with Java 8.
Looking at the original issue https://issues.apache.org/jira/browse/MNG-5895 (fixed about 4 years ago) there is a comment from December 2020 that seems to indicate problems on Windows.