fixup! modernize metadata helpers and async tests

Author: benzekrimaha

tests/functional/aws-node-sdk/test/object/putVersion.js

@@ -49,11 +49,7 @@ function putObjectVersion(s3, params, vid, cb) {
         }
     );
 
-    const promise = (async () => {
-        const res = await s3.send(command);
-        return res;
-    })();
-
+    const promise = s3.send(command);
     return cb ? promise.then(res => cb(null, res), cb) : promise;
 }