Update the lastRequestTime to prevent overlapping restarts. (#373)

When a restart occurs due to no activity set the lastRequestTime to
now to prevent ti from overlapping itself.

amazon-kinesis-client/src/main/java/software/amazon/kinesis/lifecycle/ShardConsumer.java

@@ -265,6 +265,11 @@ Throwable healthCheck() {
                     if (subscriber != null) {
                         subscriber.cancel();
                     }
+                    //
+                    // Set the last request time to now, we specifically don't null it out since we want it to trigger a
+                    // restart if the subscription still doesn't start producing.
+                    //
+                    lastRequestTime = Instant.now();
                     startSubscriptions();
                 }
             }