DERBY-6546: Database can't be dropped on Windows using the decoration of LuceneSupportPermsTest

Move database shutdown from the tearDown() method of the test case to
DropDatabaseTestSuite so that no intermediate decorators reboot the
database before it is dropped.

git-svn-id: https://svn.apache.org/repos/asf/db/derby/code/trunk@1589624 13f79535-47bb-0310-9956-ffa450edef68