Add WASM tests to CI

[matthewfeickert]

trafficstars

From @henryiii on IRIS-HEP Slack:

FYI, I added WASM wheel builds and tests to boost-histogram’s CI. We pass the whole test suite except for the threading ones (obviously) (the in-pyodide tests were partial).

This would be interesting to do for pyhf as well. It would be only a subset of the tests obviously and so would require Issue #1454 to be resolved first.

c.f. https://github.com/scikit-hep/boost-histogram/pull/850 as an example.