fix test to not create such a big automaton

git-svn-id: https://svn.apache.org/repos/asf/lucene/dev/trunk@1637448 13f79535-47bb-0310-9956-ffa450edef68
LUCENE-6054: allow repeating the empty automaton

git-svn-id: https://svn.apache.org/repos/asf/lucene/dev/trunk@1637451 13f79535-47bb-0310-9956-ffa450edef68