SuppressWithNearbyTextFilter only changes after purging cache

When using 10.10.0 from #587, the new filter generally works. However, if a file has already been analyzed once by EclipseCS, then adding or removing such a comment and saving the file will NOT lead to a change. Only after purging the cache (ctrl-3, purge) and saving again the added/removed comment will have an effect. Unclear whether that is main checkstyle or us.

Start by reproducing the issue with EclipseCS 10.10.0: analyze a file, add or remove the relevant comment, save it, then compare the result before and after using the purge command. Trace whether the stale result comes from EclipseCS or main Checkstyle; done means comment changes take effect without purging the cache.

Written by the indexing model from the issue text.