[clr-interp] Fix GitHub_9651 by allowing an I4 to be treated as a ByRef

[davidwrighton]

• This is part of allowing I4 and I to be interchangeable, since some forms of ByRef will devolve to be treated as an I
• This isn't a fully general purpose fix, but in cases where it is valid code it will make it work.

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Pull request overview

This PR fixes GitHub issue #9651 in the CoreCLR interpreter by allowing I4 (int32) values to be implicitly converted to ByRef types on 64-bit systems. The fix addresses a specific scenario where I4 and native int/ByRef can be used interchangeably in valid IL code, particularly when branching logic may assign either an int32 or an address to a native int variable.

Key Changes

• Modified the type conversion logic in the interpreter compiler to treat I4 to ByRef conversions similar to I4 to I8 (nint) conversions on 64-bit targets
• This allows IL code patterns where int32 zero and addresses are used interchangeably with native int variables

[janvorli]

LGTM, thank you!