[COM_COURSES] minor tweak to migration to attempt to prevent index conflicts
[COM_COURSES] minor tweak to migration to attempt to prevent index conflicts

zweidner/hubzero-cms,zooley/hubzero-cms,anthonyfuentes/hubzero-cms,anthonyfuentes/hubzero-cms,zooley/hubzero-cms,anthonyfuentes/hubzero-cms,zooley/hubzero-cms,zweidner/hubzero-cms,zweidner/hubzero-cms,anthonyfuentes/hubzero-cms,zweidner/hubzero-cms,zooley/hubzero-cms