remove esp-idf CI task

remove submodules

Author: bertmelis

.github/workflows/build_esp_idf.yml

@@ -0,0 +1,3 @@
+This example is for use with [Arduino as a component](https://espressif-docs.readthedocs-hosted.com/projects/arduino-esp32/en/latest/esp-idf_component.html) in the ESP-IDF framework.
+
+Be sure to follow [this section](https://espressif-docs.readthedocs-hosted.com/projects/arduino-esp32/en/latest/esp-idf_component.html#adding-local-library) about adding libraries to your project.