hotfix: fix double error message prints (#317)

This incorrect change was introduced in 598f214.

cmd/root.go

@@ -41,8 +41,12 @@ It can be used to export, import or sync entities to Kong.`,
 // Execute adds all child commands to the root command and sets
 // sflags appropriately.
 // This is called by main.main(). It only needs to happen once to the rootCmd.
-func Execute() error {
-	return rootCmd.Execute()
+func Execute() {
+	err := rootCmd.Execute()
+	if err != nil {
+		// do not print error because cobra already prints it
+		os.Exit(1)
+	}
 }
 
 //nolint:errcheck

main.go

@@ -26,11 +26,7 @@ func registerSignalHandler() {
 
 func main() {
 	registerSignalHandler()
-	err := cmd.Execute()
-	if err != nil {
-		fmt.Println(err)
-		os.Exit(1)
-	}
+	cmd.Execute()
 }
 
 func init() {