esp32: Add missing header file in esp_task.h

This commit adds a missing header file in esp_task.h
required for configMAX_PRIORITIES.

Closes #2341

components/esp32/include/esp_task.h

@@ -27,6 +27,7 @@
 #define _ESP_TASK_H_
 
 #include "sdkconfig.h"
+#include "freertos/FreeRTOSConfig.h"
 
 #define ESP_TASK_PRIO_MAX (configMAX_PRIORITIES)
 #define ESP_TASK_PRIO_MIN (0)