Fix StringFormatTrivial: Replace String.format with string templates in WebSocketModule (#56114)

Summary:
Pull Request resolved: https://github.com/facebook/react-native/pull/56114

Fixed StringFormatTrivial lint warnings in WebSocketModule.kt.

Replaced trivial String.format calls with Kotlin string templates for better performance. String.format creates a new Formatter instance on each call, while string templates are compiled to simple concatenation.

changelog: [internal] internal

Reviewed By: alanleedev

Differential Revision: D96784739

fbshipit-source-id: a6636e9448a3611a9952eb57fff71e4ad174f8c3