[CI] Emscripten wheel load fails due to LLVM 23 llvm-strip removed dylink #51487

Describe the bug, including details regarding any error messages, version, and platform.

The job test-conda-python-emscripten fails since Tue, 22 Sep at:
https://github.com/ursacomputing/crossbow/actions/runs/35673961675/job/106576406054#step:7:6209

Loading pyarrow
Failed to load pyarrow
The following error occurred while loading pyarrow:
need the dylink section to be first

followed by pyarrow already loaded from default channel and several errors (meaning it loaded pyarrow 18.1.0 from Pyodide 0.27.1 default channel)
instead of correct pyarrow already loaded from /build/python/dist/pyarrow-26.0.0.dev280-cp312-cp312-pyemscripten_2024_0_wasm32.whl - see Last successful log on Mon, 21 Sep 2026 01am GMT

Local debug shows LLVM 23 llvm-strip loses the required dylink.0,
while LLVM 22 keeps dylink.0 for the same .so.

Similar issue reported in emscripten repo: emscripten-core/emscripten#26563
LLVM 23 changed behavior of llvm-strip: llvm/llvm-project#180246

Component(s)

Continuous Integration