Allow to disable user flows

[juliusknorr]

As an administrator it should be possible to disable user flows since they can have quite some impact on the performance of a system and you might not want to give users the ability to define their own flows while still making use of the administrator level ones like file_accesscontrol/automated tagging.

cc @blizzz

[juliusknorr]

I guess just having an app config value that can be set would be fine, no need for a UI to configure this from my point of view.

[szaimen]

Isn't this already fixed with #19930 ?
So why is this still open?

[juliusknorr]

Yes, apparently "implements" didn't trigger the auto close :)