NIFI-13951: Add warn policy to dropdown selection

[sardell]

Summary

NIFI-13951

In addition to adding the missing Warn policy level as an option to the enforcement policy select, the default selection is no longer hard coded as Enforce but instead reads the value returned from the backend.

cc @pvillard31

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  • JDK 21

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[pvillard31]

I tested the fix and everything looks good to me with different rules. I'll let someone more familiar with the UI confirm that code is OK. As far as I'm concerned, I'm a +1. Thanks for the fix @sardell !

[exceptionfactory]

Sorry @sardell, I'm retracting my negative vote after a closer review. I was focused on the enforcement policy references for component validation, missing the visibility in the status section. I defer to others on frontend review.

[scottyaslan]

LGTM. I was able to create a rule and configure it to WARN.