Harden JIT 373472 regression test gating for 32-bit processes

[Copilot]

This addresses a persistent x86 Checked failure in JIT/jit64/regress/vsw/373472/test_il/test_il.dll caused by large contiguous allocations that are unreliable on 32-bit address space. The test’s existing skip logic was too narrow and did not cover all affected 32-bit processes.

• Skip condition alignment
  • Updated src/tests/JIT/jit64/regress/vsw/373472/test.cs to gate the test with PlatformDetection.Is32BitProcess (instead of IsArmProcess).
• IL twin consistency
  • Updated src/tests/JIT/jit64/regress/vsw/373472/test.il to use the same Is32BitProcess gate and aligned the ActiveIssue message text with the C# version.
• Net effect
  • Keeps intended coverage on unaffected platforms while avoiding known non-deterministic failures from 32-bit contiguous allocation limits.

[ActiveIssue(
    "Allocates large contiguous array that is not consistently available on 32-bit platforms",
    typeof(PlatformDetection),
    nameof(PlatformDetection.Is32BitProcess))]

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