[clang] [llvm] Enable running ClangReplInterpreterTests in an Emscripten environment (PR #150977)

[Vassil Vassilev via cfe-commits]

https://github.com/vgvassilev approved this pull request.

This looks like a reasonable incremental improvement to me. Thank you @mcbarton!

https://github.com/llvm/llvm-project/pull/150977