removeme: gh: add key to clone private submodules

Author: facchinm

.github/workflows/compile-examples.yml

@@ -68,6 +68,7 @@ jobs:
         uses: actions/checkout@v2
         with:
           submodules: recursive
+          token: ${{ secrets.PRIVATE_SUBMODULES_CLONE }}
 
       # The source files are in a subfolder of the ArduinoCore-API repository, so it's not possible to clone it directly to the final destination in the core
       - name: Checkout ArduinoCore-API