fixing derby tests

(in fact any DB other than hsqldb will be affected by this,
 as in the absence of hsql profile , hsql jar is not added to the maven build,
and non-core modules need it as they are tested on hsql regardless of the
core modules DB)

git-svn-id: https://svn.apache.org/repos/asf/cayenne/main/trunk@1546155 13f79535-47bb-0310-9956-ffa450edef68