Remove unused isNewNativeImage parameter from NativeImage::Open

[Copilot]

Description

The isNewNativeImage out parameter in NativeImage::Open was being populated but never used by the sole caller in AssemblyBinder::LoadNativeImage.

Changes

• Removed isNewNativeImage parameter from method signature in nativeimage.h and nativeimage.cpp
• Removed three assignments to *isNewNativeImage in the implementation
• Removed unused local variable at call site in assemblybinder.cpp

Files Changed

• src/coreclr/vm/nativeimage.h
• src/coreclr/vm/nativeimage.cpp
• src/coreclr/vm/assemblybinder.cpp

Original prompt

The isNewNativeImage parameter to NativeImage::Open does not appear to be used. Remove it.

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