Catch juju destroy-model error

It is possible, especially with Juju 2.x for list-models to return
a model that is being destroyed for us to them run destroy-model by
the time it has gone which will then fail. We need to catch this
otherwise it can cause a test run to fail.

openstack/tools/func_test_tools/common.sh

@@ -8,10 +8,10 @@ destroy_zaza_models ()
     for model in $(juju list-models| egrep -o "^zaza-\S+"|tr -d '*'); do
         if $j3; then
             juju destroy-model --no-prompt --force --no-wait \
-                                --destroy-storage $model
+                                --destroy-storage $model || true
         else
             juju destroy-model --yes --force --no-wait --destroy-storage \
-                                $model
+                                $model || true
         fi
     done
 }
@@ -43,4 +43,4 @@ apply_func_test_pr ()
         -f './test-requirements*.txt' \
         -f './src/test-requirements*.txt' \
         "$msg"
-}
+}