Fixed improper _

drivers/0x03_button/button.c

@@ -44,7 +44,7 @@ static uint32_t debounce_delay_ms = 20;
  * @param pin GPIO pin number to re-sample
  * @return bool true if the pin is still low after the debounce delay
  */
-static bool _debounce_confirm(uint32_t pin) {
+static bool debounce_confirm(uint32_t pin) {
     sleep_ms(debounce_delay_ms);
     return !gpio_get(pin);
 }
@@ -58,7 +58,7 @@ void button_init(uint32_t pin, uint32_t debounce_ms) {
 
 bool button_is_pressed(uint32_t pin) {
     if (!gpio_get(pin)) {
-        return _debounce_confirm(pin);
+        return debounce_confirm(pin);
     }
     return false;
 }