[Keyboard] fix encoder_update_user for nullbitsco/nibble (#13451)

keyboards/nullbitsco/nibble/keymaps/oled_status/keymap.c

@@ -81,7 +81,7 @@ bool process_record_user(uint16_t keycode, keyrecord_t *record) {
 }
 
 
-void encoder_update_user(uint8_t index, bool clockwise) {
+bool encoder_update_user(uint8_t index, bool clockwise) {
     if (clockwise) {
         tap_code(KC_VOLU);
 #ifdef OLED_DRIVER_ENABLE
@@ -93,6 +93,7 @@ void encoder_update_user(uint8_t index, bool clockwise) {
         process_record_encoder_oled(KC_VOLD);
 #endif
     }
+    return true;
 }
 
 void matrix_init_user(void) {