Add macOS simulator build to pipelines (#162)

- GitHub actions changed to build simulator on macOS (it's broken, but at least we get a good code portability check for now!)
- `Buildscripts/` shell scripts updated to use `/bin/sh` so it works on macOS too
- Various includes fixed in various subprojects so the code is more portable

CMakeLists.txt

@@ -70,7 +70,6 @@ if (NOT DEFINED ENV{ESP_IDF_VERSION})
 endif()
 
 if (NOT DEFINED ENV{ESP_IDF_VERSION})
-
     # FreeRTOS
     set(FREERTOS_CONFIG_FILE_DIRECTORY ${PROJECT_SOURCE_DIR}/Boards/Simulator/Source CACHE STRING "")
     set(FREERTOS_PORT GCC_POSIX CACHE STRING "")