fix: implement workaround for known GPIO issue

GPIO 36 and 39 trigger false ISR's in esp-idf v4.2.0.
This caused the button task to run too much, starving other tasks.

See espressif/esp-idf#1096.

src/util/buttons.cpp

@@ -26,6 +26,14 @@ namespace Buttons
          */
         void IRAM_ATTR ISRHandlerGPIO(void *pvParams)
         {
+            auto button = reinterpret_cast<Button *>(pvParams);
+
+            // Button was not actually pressed.
+            // This is a workaround for a know error for some GPIO's with the ISR in esp-idf v4.4.0.
+            // See https://github.com/espressif/esp-idf/issues/1096.
+            if (gpio_get_level(button->gpioNum) != button->trigger)
+                return;
+
             xQueueSendFromISR(s_gpioEventQueue, pvParams, NULL);
         }