Wasm spmi use checked jit

[AndyAyersMS]

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[AndyAyersMS]

@dotnet/wasm-contrib PTAL
fyi @dotnet/jit-contrib

Collection pipeline is working but is using a release jit. Switch to checked.

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Pull request overview

This PR adjusts the SuperPMI collection pipeline so the browser/wasm corelib crossgen2 collection uses a Checked wasm cross-targeting JIT (enabling JIT asserts during collection), and ensures the required clr.wasmjit outputs are present in the Checked build artifacts.

Changes:

• Build clr.wasmjit as part of the Checked windows_x64/linux_x64 build so the wasm cross-targeting JIT is available in the Checked Core_Root artifacts.
• Stop building clr.wasmjit as part of the Release windows_x64/linux_x64 build (since the wasm collection no longer runs under buildConfig: release).
• Switch the browser/wasm corelib crossgen2 SuperPMI collection job from buildConfig: release to buildConfig: checked.

[AndyAyersMS]

Verified by running the internal pipeline and downloading on a local machine:

> python superpmi.py replay -target_os browser -target_arch wasm

[15:01:48] ================ Logging to c:\spmi\superpmi.1105.log
[15:01:48] Overriding 'mch_arch' to 'x64'
[15:01:49] Overriding 'altjit' to True for wasm cross-target JIT
[15:01:49] Using JIT/EE Version from jiteeversionguid.h: 31a04b06-915e-42a0-bbd2-c9c397677ae5
[15:01:49] Found download cache directory "c:\spmi\mch\31a04b06-915e-42a0-bbd2-c9c397677ae5.browser.x64" and --force_download not set; skipping download
[15:01:49] SuperPMI replay
[15:01:49] JIT Path: C:\repos\runtime4\artifacts\tests\coreclr\windows.x64.Checked\Tests\Core_Root\clrjit_universal_wasm_x64.dll
[15:01:49] Using MCH files:
[15:01:49]   c:\spmi\mch\31a04b06-915e-42a0-bbd2-c9c397677ae5.browser.x64\corelib.crossgen2.windows.x64.checked.mch
[15:01:49] Running SuperPMI replay of c:\spmi\mch\31a04b06-915e-42a0-bbd2-c9c397677ae5.browser.x64\corelib.crossgen2.windows.x64.checked.mch
[15:01:57] Clean SuperPMI replay (24887 contexts processed)
[15:01:57] Replay summary:
[15:01:57]   All replays clean