flaky TestResourceManagerServicePeerInbound test

[marten-seemann]

=== RUN   TestResourceManagerServicePeerInbound
      rcmgr_test.go:205: stream reset
      rcmgr_test.go:205: stream reset
      rcmgr_test.go:214: 
          	Error Trace:	echo_test.go:53
          	            				rcmgr_test.go:214
          	Error:      	Not equal: 
          	            	expected: itest.EchoStatus{StreamsIn:7, EchosIn:6, EchosOut:6, IOErrors:0, ResourceServiceErrors:1, ResourceReservationErrors:0}
          	            	actual  : itest.EchoStatus{StreamsIn:7, EchosIn:5, EchosOut:5, IOErrors:0, ResourceServiceErrors:2, ResourceReservationErrors:0}
          	            	
          	            	Diff:
          	            	--- Expected
          	            	+++ Actual
          	            	@@ -2,6 +2,6 @@
          	            	  StreamsIn: (int) 7,
          	            	- EchosIn: (int) 6,
          	            	- EchosOut: (int) 6,
          	            	+ EchosIn: (int) 5,
          	            	+ EchosOut: (int) 5,
          	            	  IOErrors: (int) 0,
          	            	- ResourceServiceErrors: (int) 1,
          	            	+ ResourceServiceErrors: (int) 2,
          	            	  ResourceReservationErrors: (int) 0
          	Test:       	TestResourceManagerServicePeerInbound
  --- FAIL: TestResourceManagerServicePeerInbound (2.01s)