fix flaky test

contrib/gocql/gocql/observer_test.go

@@ -379,7 +379,7 @@ func TestObserver_Connect(t *testing.T) {
 				}
 			}
 			assert.NotEmpty(t, okSpans)
-			assert.NotEmpty(t, errSpans)
+			// the errSpans slice might be empty or not, so we don't assert any length to avoid flakiness.
 
 			for _, span := range spans {
 				// this information should be present in all spans.