[compiler] Remove redundant InferMutableContextVariables (#32097)

This removes special casing for `PropertyStore` mutability inference
within FunctionExpressions.
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[//]: # (BEGIN SAPLING FOOTER)
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with [ReviewStack](https://reviewstack.dev/facebook/react/pull/32097).
* #32287
* #32104
* #32098
* __->__ #32097