Update to go1.16

pkg/cli/loader_file.go

@@ -1,7 +1,6 @@
 package cli
 
 import (
-	"io/ioutil"
 	"os"
 	"strings"
 
@@ -56,7 +55,7 @@ func (f *FileLoader) Load(args []string, cmd *cli.Command) (bool, error) {
 	logger := log.WithoutContext()
 	logger.Printf("Configuration loaded from file: %s", configFile)
 
-	content, _ := ioutil.ReadFile(configFile)
+	content, _ := os.ReadFile(configFile)
 	logger.Debug(string(content))
 
 	return true, nil