fix: consistent use of client var

main.go

@@ -96,10 +96,12 @@ Note: Use "" around everything but numbers, also wrap json in ''
 			os.Exit(1)
 		}
 		data := args[0]
-		res, err := http.Post(resource, "application/json; charset=UTF-8", bytes.NewBufferString(data))
+		req, err := http.NewRequest(http.MethodPost, resource, bytes.NewBufferString(data))
 		if err != nil {
 			log.Fatal(err)
 		}
+		req.Header.Set("Content-Type", "application/json; charset=UTF-8")
+		res, err := client.Do(req)
 		defer res.Body.Close()
 		body, err := ioutil.ReadAll(res.Body)
 		if err != nil {