oauthutil: suppress ERROR message when doing remote config

Before this change doing a remote config using rclone authorize gave
this error.  The token is saved a bit later anyway so the error is
needlessly confusing.

    ERROR : Failed to save new token in config file: section 'remote' not found.

This commit suppresses that error.

https://forum.rclone.org/t/onedrive-for-business-failed-to-save-token/8061

lib/oauthutil/oauthutil.go

@@ -358,7 +358,7 @@ func doConfig(id, name string, m configmap.Mapper, errorHandler func(*http.Reque
 			if err != nil {
 				return err
 			}
-			return PutToken(name, m, token, false)
+			return PutToken(name, m, token, true)
 		}
 	case TitleBarRedirectURL:
 		useWebServer = automatic