[FAB] set AppBuilder to update_perms=False (#7561)

* [FAB] set AppBuilder to update_perms=False

Upon start, by default, FAB tries to go and update the permission list
in the database based on the list of views, models and menu items that
exist in the code.

Really this should happen once per deployment/upgrade and
not in module scope, so we have `superset init` for this.

The intent was always to set to False by default, but I think we forgot
to add this flag back in
#7323

* Add superset init to tox

(cherry picked from commit eb42936)

superset/__init__.py

@@ -203,6 +203,7 @@ def index(self):
         base_template='superset/base.html',
         indexview=MyIndexView,
         security_manager_class=custom_sm,
+        update_perms=False,  # Run `superset init` to update FAB's perms
     )
 
 security_manager = appbuilder.sm

tox.ini

@@ -46,6 +46,7 @@ require-code = true
 [testenv]
 commands =
     {toxinidir}/superset/bin/superset db upgrade
+    {toxinidir}/superset/bin/superset init
     nosetests tests/load_examples_test.py
     nosetests -e load_examples_test {posargs}
 deps =