Update go to 1.25 (#875)

Closes #872

* update go to 1.25

* update deprecated gomock

* remove deprecated ioutil

* update (and fix) ci

* add golang lint (as warning)

* enable formatters + freeze golang version

collector/pkg/collector/base.go

@@ -3,9 +3,10 @@ package collector
 import (
 	"bytes"
 	"encoding/json"
-	"github.com/sirupsen/logrus"
 	"net/http"
 	"time"
+
+	"github.com/sirupsen/logrus"
 )
 
 var httpClient = &http.Client{Timeout: 60 * time.Second}
@@ -14,17 +15,6 @@ type BaseCollector struct {
 	logger *logrus.Entry
 }
 
-func (c *BaseCollector) getJson(url string, target interface{}) error {
-
-	r, err := httpClient.Get(url)
-	if err != nil {
-		return err
-	}
-	defer r.Body.Close()
-
-	return json.NewDecoder(r.Body).Decode(target)
-}
-
 func (c *BaseCollector) postJson(url string, body interface{}, target interface{}) error {
 	requestBody, err := json.Marshal(body)
 	if err != nil {