ci: add job to test with Emscripten #4030

Job	Run time
vanilla-build (windows-latest, 3.11)	5m 15s
vanilla-build (ubuntu-latest, 3.11)	3m 30s
build (windows-latest, 3.8)	7m 39s
vanilla-build (macos-latest, 3.11)	2m 36s
build (windows-latest, 3.9)	7m 47s
numpy1-build (windows-latest, 3.11)	3m 37s
build (windows-latest, 3.10)	8m 16s
numpy1-build (ubuntu-latest, 3.11)	2m 23s
build (windows-latest, 3.11)	7m 44s
numpy1-build (macos-latest, 3.11)	1m 35s
pyodide-build	2m 9s
build (windows-latest, 3.12)	7m 42s
build (macos-latest, 3.8)	4m 42s
build (macos-latest, 3.9)	4m 5s
build (macos-latest, 3.10)	4m 57s
build (macos-latest, 3.11)	5m 38s
build (macos-latest, 3.12)	3m 48s
build (ubuntu-latest, 3.8)	6m 4s
build (ubuntu-latest, 3.9)	5m 9s
build (ubuntu-latest, 3.10)	5m 50s
build (ubuntu-latest, 3.11)	4m 33s
build (ubuntu-latest, 3.12)	5m 38s
	1h 50m 37s

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