Rename loop var, underscores are not used to mark unused vars elsewhere in this code

Author: wpessers

packages/instrumentation-aws-lambda/test/lambda-test/sync.js

@@ -21,7 +21,7 @@ exports.handler = function (event, context, callback) {
 
 exports.sqshandler = function (event, context, callback) {
   // Dummy forEach loop, to trigger sqs instrumentation
-  event.Records.forEach(_r => {});
+  event.Records.forEach(r => {});
   callback(null, 'ok');
 };