Add unit tests for LUGroupRemove
Add unit tests for LUGroupRemove

This patch adds unit test coverage for LUGroupRemove.

Signed-off-by: Thomas Thrainer <98bdeac947eb8ca18146e9ce7f092788ec242cd1@google.com>
Reviewed-by: Guido Trotter <f62ca4d5358bdaeef0e50e57f9f7e231de63727e@google.com>

onponomarev/ganeti,yiannist/ganeti,ganeti/ganeti,yiannist/ganeti,mbakke/ganeti,grnet/snf-ganeti,bitemyapp/ganeti,leshchevds/ganeti,leshchevds/ganeti,apyrgio/ganeti,andir/ganeti,apyrgio/ganeti,apyrgio/snf-ganeti,ganeti-github-testing/ganeti-test-1,onponomarev/ganeti,dimara/ganeti,bitemyapp/ganeti,grnet/snf-ganeti,ganeti/ganeti,apyrgio/snf-ganeti,ganeti-github-testing/ganeti-test-1,mbakke/ganeti,ganeti/ganeti,leshchevds/ganeti,andir/ganeti,dimara/ganeti,yiannist/ganeti,mbakke/ganeti,andir/ganeti