[1.8>1.9] [MERGE #4684 @MikeHolman] fix assert in JIT data serialization
[1.8>1.9] [MERGE #4684 @MikeHolman] fix assert in JIT data serialization

Merge pull request #4684 from MikeHolman:serializedassert

We may have multiple codegen calls for same entrypoint, so replace the old JIT data if this happens

OS: 15845157

Microsoft/ChakraCore,Microsoft/ChakraCore,Microsoft/ChakraCore,Microsoft/ChakraCore,Microsoft/ChakraCore,Microsoft/ChakraCore