Can edit a build config to a strategy that isn't allowed by policy - builds still fail correctly

[jwforres]

If I apply the policy changes to restrict certain build strategies, I can create a BC with an allowed strategy and then edit the BC to use a restricted strategy, that edit should fail. Instead it allows the modification. It does still correctly prevent the builds from being launched.

[csrwng]

@bparees or @jwforres can you change the priority of this issue to P1? It allows escalating privileges on a node. You don't need to explicitly be able to create a build once you've created a build config with a forbidden type. An image change trigger can do that for you.