updating platform for CI

Author: andreagilardoni

.github/workflows/compile-examples.yml

@@ -34,7 +34,7 @@ jobs:
         board:
           - fqbn: arduino:mbed:envie_m7
             platforms: |
-              - name: arduino:mbed
+              - name: arduino:mbed_portenta
             libraries: |
               - name: Arduino_DebugUtils
             sketch-paths: |