NIFI-15994: Made UpdateAttribute advanced settings focus the add rule

[Freedom9339]

Summary

NIFI-15994: Made UpdateAttribute advanced settings focus the add rule form. Currently, adding a new rule adds the new rule form at the very bottom, and If there are enough rules that cover the screen, the form will not be visible and it appears as if the add button isn't working. With this fix, the focus is moved to the form when a rule is added.

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  • JDK 21
  • JDK 25

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