test: add missing await

Add missing `await` in
`test/parallel/test-inspector-async-stack-traces-promise-then.js`.

PR-URL: nodejs#54828
Reviewed-By: Jake Yuesong Li <jake.yuesong@gmail.com>
Reviewed-By: James M Snell <jasnell@gmail.com>
Reviewed-By: Trivikram Kamat <trivikr.dev@gmail.com>
Reviewed-By: Moshe Atlow <moshe@atlow.co.il>
Reviewed-By: Richard Lau <rlau@redhat.com>
Reviewed-By: Michael Dawson <midawson@redhat.com>

test/parallel/test-inspector-async-stack-traces-promise-then.js

@@ -31,7 +31,7 @@ async function runTests() {
       'params': { 'patterns': [] } },
     { 'method': 'Runtime.runIfWaitingForDebugger' },
   ]);
-  session.send({ method: 'NodeRuntime.disable' });
+  await session.send({ method: 'NodeRuntime.disable' });
 
   await session.waitForBreakOnLine(0, '[eval]');
   await session.send({ 'method': 'Debugger.resume' });