Rework servers load-balancer to use the WRR

Co-authored-by: Kevin Pollet <pollet.kevin@gmail.com>

pkg/redactor/redactor_config_test.go

@@ -82,8 +82,8 @@ func init() {
 						Scheme:          "foo",
 						Path:            "foo",
 						Port:            42,
-						Interval:        "foo",
-						Timeout:         "foo",
+						Interval:        ptypes.Duration(111 * time.Second),
+						Timeout:         ptypes.Duration(111 * time.Second),
 						Hostname:        "foo",
 						FollowRedirects: boolPtr(true),
 						Headers: map[string]string{
@@ -92,7 +92,7 @@ func init() {
 					},
 					PassHostHeader: boolPtr(true),
 					ResponseForwarding: &dynamic.ResponseForwarding{
-						FlushInterval: "foo",
+						FlushInterval: ptypes.Duration(111 * time.Second),
 					},
 					ServersTransport: "foo",
 					Servers: []dynamic.Server{