chore: fix serve_watch_all test (#26725)

It's been failing a ton lately, it looks like the test is just
incorrectly using TS syntax in a JS file
https://github.com/denoland/deno/actions/runs/11672972415/job/32502710624?pr=26724#step:43:2791

I'm not really sure how this ever passes

Author: nathanwhit

tests/integration/watcher_tests.rs

@@ -572,16 +572,19 @@ async fn serve_watch_all() {
   let main_file_to_watch = t.path().join("main_file_to_watch.js");
   main_file_to_watch.write(
     "export default {
-      fetch(_request: Request) {
+      fetch(_request) {
         return new Response(\"aaaaaaqqq!\");
       },
     };",
   );
 
+  let another_file = t.path().join("another_file.js");
+  another_file.write("");
+
   let mut child = util::deno_cmd()
     .current_dir(t.path())
     .arg("serve")
-    .arg("--watch=another_file.js")
+    .arg(format!("--watch={another_file}"))
     .arg("-L")
     .arg("debug")
     .arg(&main_file_to_watch)
@@ -596,37 +599,40 @@ async fn serve_watch_all() {
   // Change content of the file
   main_file_to_watch.write(
     "export default {
-      fetch(_request: Request) {
+      fetch(_request) {
         return new Response(\"aaaaaaqqq123!\");
       },
     };",
   );
   wait_contains("Restarting", &mut stderr_lines).await;
   wait_for_watcher("main_file_to_watch.js", &mut stderr_lines).await;
 
-  let another_file = t.path().join("another_file.js");
   another_file.write("export const foo = 0;");
   // Confirm that the added file is watched as well
   wait_contains("Restarting", &mut stderr_lines).await;
+  wait_for_watcher("main_file_to_watch.js", &mut stderr_lines).await;
 
   main_file_to_watch
     .write("import { foo } from './another_file.js'; console.log(foo);");
   wait_contains("Restarting", &mut stderr_lines).await;
+  wait_for_watcher("main_file_to_watch.js", &mut stderr_lines).await;
   wait_contains("0", &mut stdout_lines).await;
 
   another_file.write("export const foo = 42;");
   wait_contains("Restarting", &mut stderr_lines).await;
+  wait_for_watcher("main_file_to_watch.js", &mut stderr_lines).await;
   wait_contains("42", &mut stdout_lines).await;
 
   // Confirm that watch continues even with wrong syntax error
   another_file.write("syntax error ^^");
 
   wait_contains("Restarting", &mut stderr_lines).await;
   wait_contains("error:", &mut stderr_lines).await;
+  wait_for_watcher("main_file_to_watch.js", &mut stderr_lines).await;
 
   main_file_to_watch.write(
     "export default {
-      fetch(_request: Request) {
+      fetch(_request) {
         return new Response(\"aaaaaaqqq!\");
       },
     };",