tests: fix truncated group name

/usr/lib64/python2.6/site-packages/sqlalchemy/engine/default.py:299: Warning: Data truncated for column 'group_name' at row 1
  cursor.execute(statement, parameters)

Change-Id: I5cde7d277d9890dfe63621b80711ab2657f69b5e
Merge "tests: fix truncated group name" into develop