chore: update to go1.19

integration/keepalive_test.go

@@ -77,7 +77,7 @@ func (s *KeepAliveSuite) TestShouldRespectConfiguredBackendHttpKeepAliveTime(c *
 	}()
 
 	server := httptest.NewUnstartedServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
-		w.WriteHeader(200)
+		w.WriteHeader(http.StatusOK)
 	}))
 
 	server.Config.ConnState = func(conn net.Conn, state http.ConnState) {