This change will install specified packages of Emscripten and set up
the build environment for making binary artifacts of WebAssembly
Task-number: QTQAINFRA-1972
Change-Id: Ia5df6c208ea8f29ca8948f0273f321a59fc694a2
Reviewed-by: Eskil Abrahamsen Blomfeldt <eskil.abrahamsen-blomfeldt@qt.io>