Add more time buffer so that the alarm will be executed as expected in tests. It will fix the flaky EndpointIdRotateWhenHighVizAdvertisementAgainForAWhile test.

PiperOrigin-RevId: 399248463

cpp/core/internal/client_proxy_test.cc

@@ -530,7 +530,7 @@ TEST_F(ClientProxyTest,
 
   // Wait to expire and then advertise.
   absl::SleepFor(ClientProxy::kHighPowerAdvertisementEndpointIdCacheTimeout +
-                 absl::Milliseconds(10));
+                 absl::Milliseconds(100));
   Endpoint advertising_endpoint_2 = StartAdvertising(
       &client1_, advertising_connection_listener_, advertising_options);