Fix wasm build issues introduced by switching to wasi-sdk (#4407)

* Don't shell out for extracting tar.gz files

* Avoid wasi-sdk adding dependency on libc.so

* Clippy

* Fix -nostdlib flag

xtask/src/main.rs

@@ -123,9 +123,6 @@ struct GenerateFixtures {
     /// Generates the parser to WASM
     #[arg(long, short)]
     wasm: bool,
-    /// Run emscripten via docker even if it is installed locally.
-    #[arg(long, short, requires = "wasm")]
-    docker: bool,
 }
 
 #[derive(Args)]