wasm jobs does not set CROSS_EMULATOR in `gen_ci.hs`
It is quite confusing that the wasm jobs set CROSS_EMULATOR
somewhere outside of gen_ci.hs
.
In fact, it's confusing that any build configuration is not specified in either hadrian or the CI generation script. It should all be there so it is uniform with the other build jobs.
Therefore the proposal is that anything which affects the running of the CI script should be set in gen_ci.hs
rather than a separate script.