Show Notification no longer generates a random Identifier when Identifier is set to an empty value

### Description Please see the video below, which illustrates the issue: https://github.com/user-attachments/assets/425a6f31-ad18-4556-8ccc-13973b7e031e 1. I run `Show Notification` with a generic title and message, and `Is Time Sensitive` **on**. I do not change the `Identifier`. The notification appears immediately upon running the shortcut. 2. I set a random letter as the Identifier and run the shortcut again. The notification appears immediately. 3. I delete the Identifier and run the shortcut. No notification appears. This issue also breaks shortcuts that pass a variable as the `Identifier`, relying on the Action to generate a random value when the variable is blank. I believe the change in behavior was introduced with version 3.9.0 (116). Thank you! ### macOS/iOS version 26.2 RC ### Shortcut URL _No response_