SOLR=6873: Lib relative path is incorrect for techproduct configset

git-svn-id: https://svn.apache.org/repos/asf/lucene/dev/branches/branch_5x@1647832 13f79535-47bb-0310-9956-ffa450edef68
SOLR-6864: Improved tests, added useColdSearcher test case

git-svn-id: https://svn.apache.org/repos/asf/lucene/dev/branches/branch_5x@1647837 13f79535-47bb-0310-9956-ffa450edef68