AS testsuite test targets don't work on windows

Since we've switched to maven repository classpath for testsuite classpath, the classpath got too long to work on windows.
So, it either has to be shorter or a manifest-only jar can be created that would reference all the jars and dirs.
The problem with the manifest-only jar is that there must be relative path from the jar location to all the other jars and dirs that need to be included in the classpath. Taking into account that the relative path might not exist (e.g. the AS checkout and maven local repo can be on different drives) the jar might not work.

(Although, right now on my windows machine fixed it with generating the manifest-only jar.)