update prometheus dependencies (#5520)

Signed-off-by: junot <junotxiang@kubesphere.io>

vendor/github.com/prometheus-community/prom-label-proxy/injectproxy/utils.go

@@ -0,0 +1,32 @@
+// Copyright 2020 The Prometheus Authors
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package injectproxy
+
+import (
+	"encoding/json"
+	"log"
+	"net/http"
+)
+
+func prometheusAPIError(w http.ResponseWriter, errorMessage string, code int) {
+	w.Header().Set("Content-Type", "application/json; charset=utf-8")
+	w.Header().Set("X-Content-Type-Options", "nosniff")
+	w.WriteHeader(code)
+
+	res := map[string]string{"status": "error", "errorType": "prom-label-proxy", "error": errorMessage}
+
+	if err := json.NewEncoder(w).Encode(res); err != nil {
+		log.Printf("error: Failed to encode json: %v", err)
+	}
+}