Fix mysql prompt
Fix mysql prompt

The mysql command can be executed as user - as it's done in the
rest of the guide. Change prompt.

Change-Id: I9c1cc3a7e54a7cbf4524279220c880308e202bb1
Closes-Bug: #1341187

Akasurde/openstack-manuals,saeki-masaki/openstack-manuals,potsmaster/openstack-manuals,openstack/openstack-manuals,kairoaraujo/openstack-manuals,Akasurde/openstack-manuals,AlekhyaMallina-Vedams/openstack-manuals,potsmaster/openstack-manuals,gongysh2004/openstack-manual,saeki-masaki/openstack-manuals,AlekhyaMallina-Vedams/openstack-manuals,gongysh2004/openstack-manual,openstack/openstack-manuals,AlekhyaMallina-Vedams/openstack-manuals,openstack/openstack-manuals,kairoaraujo/openstack-manuals,openstack/openstack-manuals