test: remove custom message from assertion

The custom message means that the values involved are not reported.
Remove the custom message for a more detailed error message.

PR-URL: https://github.com/nodejs/node/pull/16824
Reviewed-By: Colin Ihrig <cjihrig@gmail.com>
Reviewed-By: Anatoli Papirovski <apapirovski@mac.com>
Reviewed-By: Gireesh Punathil <gpunathi@in.ibm.com>
Reviewed-By: Rich Trott <rtrott@gmail.com>

test/addons/async-hooks-promise/test.js

@@ -34,8 +34,7 @@ const hook1 = async_hooks.createHook({
 // Check that the internal field returns the same PromiseWrap passed to init().
 assert.strictEqual(
   binding.getPromiseField(Promise.resolve(1)),
-  pwrap,
-  'Unexpected PromiseWrap');
+  pwrap);
 
 hook1.disable();