Fix: Add debounce to favicon update

[chakflying]

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Description

favico.js has a queue limit of 100 (source). Too many monitors going down at the same time will cause error:

Uncaught (in promise) Error: Error setting badge. Message: Too many badges requests in queue.
    _readyCb favico.js:337
    badge favico.js:341
    down socket.js:763

This attempts to add a simple debounce to the favicon update.

Type of change

• Bug fix (non-breaking change which fixes an issue)

Checklist

• My code follows the style guidelines of this project
• I ran ESLint and other linters for modified files
• I have performed a self-review of my own code and tested it
• I have commented my code, particularly in hard-to-understand areas
  (including JSDoc for methods)
• My changes generate no new warnings
• My code needed automated testing. I have added them (this is optional task)

Screenshots (if any)