Update AnimatedColor-test.js

## Summary:

Fixed an issue in AnimatedColor.js where _listenerCount could become 
negative during unmount, causing native subscription memory leaks...

## Changelog:

[GENERAL] [FIXED] - Prevent negative listener count in AnimatedColor 
causing native subscription memory leaks after __detach()

## Test Plan:

Added regression tests in AnimatedColor-test.js covering:
- _listenerCount does not go negative after __detach() + removeListener()
- removeListener after removeAllListeners is a safe no-op
- Native subscription cleanup when count reaches 0

Author: mhdamirhamza