Correct the help sting of volume-type-delete
Correct the help sting of volume-type-delete

Change-Id: I10b1bd6d42e4085dc73572f05ed893385ca3e139

JioCloud/python-novaclient,mat128/python-novaclient,CCI-MOC/python-novaclient,JioCloud/python-novaclient,akash1808/python-novaclient,Shihta/python-novaclient,guptaankita/python-novaclient,takeshineshiro/python-novaclient,Shihta/python-novaclient,takeshineshiro/python-novaclient,CCI-MOC/python-novaclient,guptaankita/python-novaclient,akash1808/python-novaclient,mat128/python-novaclient