fix: remove cached modules completely from require cache in disable()

[wenboyu2]

Problem: We noticed memory leak with require cache when using mockery.enable({useCleanCache: true}). disalbe() doesn't clean up the cache completely.

Solution: Remove module references from m._cache as well as the module's parents' children.

[pklingem]

@mfncooper we've verified this PR fixes the memory leak we were seeing. Any chance of getting this merged?