Fix std feature in wasm-encoder

[ark0f]

No description provided.

[alexcrichton]

Thanks for the PR! Could you describe a bit more what's going on here? I'm not sure what the fix is and I'm also not familiar enough with the leb128fmt crate to know how best it solves such a problem off the top of my head.

[ark0f]

Could you describe a bit more what's going on here?

I found out that wasm-encoder does not switch std feature of its wasmparser dependency after #1938. I also disabled std feature in the workspace for wasmparser (and wasm-encoder for consistency) so it can manage this feature properly.

I'm also not familiar enough with the leb128fmt crate

leb128 doesn't support no-std when leb128fmt does

[alexcrichton]

Ok sounds good, thanks! Can you update CI configuration around here to check that wasm-encoder builds for no_std? Looks like we forgot that from before which is why this wasn't caught earlier.

I'll take some time tomorrow to review the leb128fmt crate as well as we want to review new dependencies before including them.

[alexcrichton]

Thanks again for your work here!