[core-amqp][test] add explicit type for clearTimeout parameter (Azure#21892)

The compiler is having problem figuring it out in latest rush update --full run.

Author: jeremymeng

sdk/core/core-amqp/test/requestResponse.spec.ts

@@ -604,7 +604,7 @@ describe("RequestResponseLink", function () {
 
     beforeEach(() => {
       clearTimeoutCalledCount = 0;
-      _global.clearTimeout = (tid) => {
+      _global.clearTimeout = (tid: NodeJS.Timeout) => {
         clearTimeoutCalledCount++;
         return originalClearTimeout(tid);
       };