Updates zig9 to zig

Referenced in https://github.com/rtfeldman/roc/pull/1905

compiler/build/src/link.rs

@@ -878,7 +878,7 @@ fn link_wasm32(
     let zig_str_path = find_zig_str_path();
     let wasi_libc_path = find_wasi_libc_path();
 
-    let child = Command::new("zig9")
+    let child = Command::new("zig")
         // .env_clear()
         // .env("PATH", &env_path)
         .args(&["build-exe"])

compiler/test_gen/src/helpers/llvm.rs

@@ -367,7 +367,7 @@ pub fn helper_wasm<'a>(
 
     use std::process::Command;
 
-    Command::new("zig9")
+    Command::new("zig")
         .current_dir(dir_path)
         .args(&[
             "wasm-ld",

examples/hello-web/.gitignore

@@ -1,2 +1,2 @@
-hello-web
+hello-web.wasm
 *.wat