[wasm] `warning: return type of 'main' is not 'int' ' [-Wmain-return-type]`

> But it feels like a GHC bug..maybe it is and I should cut GHC gitlab a ticket? But I figured I’d ask the crowd first In general, for little things like this with the Wasm backend, where you don’t want to jump straight in to opening a GHC ticket, I’d ask in the Matrix room. Anyway, I don’t think I’ve seen this warning before, but I am now mostly using Haskell.nix for Wasm builds instead of the official flake. @TerrorJack might know.