[event-hubs] investigate flaky tests (Azure#13460)

* [event-hubs] investigate flaky tests

* try to make logging work

* more logging

* more logging

* increase time for subscription1 to recover to 20s from 10s since it can take 10s to attempt to reread from a partition that was disconnected

* now remove logging and run test 20 times to see if it is fixed

* revert .it

* make test shorter!

Author: chradek

sdk/eventhub/event-hubs/test/public/eventHubConsumerClient.spec.ts

@@ -291,12 +291,14 @@ describe("EventHubConsumerClient", () => {
         const consumerClient1 = new EventHubConsumerClient(
           EventHubConsumerClient.defaultConsumerGroupName,
           service.connectionString,
-          service.path
+          service.path,
+          { loadBalancingOptions: { updateIntervalInMs: 1000 } }
         );
         const consumerClient2 = new EventHubConsumerClient(
           EventHubConsumerClient.defaultConsumerGroupName,
           service.connectionString,
-          service.path
+          service.path,
+          { loadBalancingOptions: { updateIntervalInMs: 1000 } }
         );
 
         clients.push(consumerClient1, consumerClient2);