[PLG_GROUPS_MEMBERS] Fixed issue when deleting member role.
[PLG_GROUPS_MEMBERS] Fixed issue when deleting member role.

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