remove the keystone bash completion install step

keytone has removed it's CLI and will release a new version
when Newton begins. As part of the removal process we also
need to remove the bash completion script, which is currently
failing devstack gates.

Change-Id: I132b862bde5b4173bf34beae12a7a882f5a96314

lib/keystone

@@ -523,7 +523,6 @@ function install_keystoneclient {
     if use_library_from_git "python-keystoneclient"; then
         git_clone_by_name "python-keystoneclient"
         setup_dev_lib "python-keystoneclient"
-        sudo install -D -m 0644 -o $STACK_USER {${GITDIR["python-keystoneclient"]}/tools/,/etc/bash_completion.d/}keystone.bash_completion
     fi
 }