SOLR-6427: HdfsCollectionsAPIDistributedZkTest can fail because it tries to use an hdfs location with the file system based spellchecker which results in it trying to write to an illegal filesystem location.

git-svn-id: https://svn.apache.org/repos/asf/lucene/dev/branches/branch_4x@1620304 13f79535-47bb-0310-9956-ffa450edef68