reduce accidental user-button press probability

Core/Src/main.c

@@ -224,7 +224,7 @@ int main(void)
 		write_data_byte('0' + (char) current_digit);
 	}
 
-	HAL_Delay(70);
+	HAL_Delay(10);
     /* USER CODE END WHILE */
 
     /* USER CODE BEGIN 3 */

Core/Src/stm32f4xx_it.c

@@ -207,7 +207,7 @@ void EXTI0_IRQHandler(void)
 
   change *= -1;
 
-  for (int i = 0; i < 200000; i++) {asm("nop");}
+  for (int i = 0; i < 400000; i++) {asm("nop");}
   /* USER CODE END EXTI0_IRQn 0 */
   HAL_GPIO_EXTI_IRQHandler(GPIO_PIN_0);
   /* USER CODE BEGIN EXTI0_IRQn 1 */