Add opta compile example workflow

Author: pennam

.github/workflows/compile-examples.yml

@@ -49,6 +49,15 @@ jobs:
             sketch-paths: |
               - examples/OTA_Qspi_Flash
               - examples/OTA_Usage_Portenta
+          - fqbn: arduino:mbed_opta:opta
+            platforms: |
+              - name: arduino:mbed_opta
+            libraries: |
+              - name: Arduino_DebugUtils
+            sketch-paths: |
+              - examples/OTA_Qspi_Flash
+              - examples/OTA_Qspi_Flash_Ethernet
+              - examples/OTA_Usage_Portenta
 
     steps:
       - name: Checkout