Add ESP32 board to "Compile Examples" CI workflow

ESP32 support has been added to the library, so the examples compilation smoke test should be done for this architecture
as well.

Author: per1234

.github/workflows/compile-examples.yml

@@ -46,7 +46,8 @@ jobs:
           {"fqbn": "arduino:samd:mkrnb1500", "type": "nb"},
           {"fqbn": "arduino:mbed:envie_m4", "type": "mbed"},
           {"fqbn": "arduino:mbed:envie_m7", "type": "mbed"},
-          {"fqbn": "esp8266:esp8266:huzzah", "type": "esp8266"}
+          {"fqbn": "esp8266:esp8266:huzzah", "type": "esp8266"},
+          {"fqbn": "esp32:esp32:esp32", "type": "esp32"}
         ]
 
         # make board type-specific customizations to the matrix jobs
@@ -132,6 +133,15 @@ jobs:
                 source-url: https://arduino.esp8266.com/stable/package_esp8266com_index.json
             libraries:
             sketch-paths:
+          # ESP32 boards
+          - board:
+              type: "esp32"
+            platforms: |
+              # Install ESP32 platform via Boards Manager
+              - name: esp32:esp32
+                source-url: https://raw.githubusercontent.com/espressif/arduino-esp32/gh-pages/package_esp32_index.json
+            libraries:
+            sketch-paths:
 
     steps:
       - name: Checkout
@@ -162,6 +172,10 @@ jobs:
         run: |
           mv "${{ env.ARDUINOCORE_API_STAGING_PATH }}/api" "${{ env.ARDUINOCORE_MBED_STAGING_PATH }}/cores/arduino"
 
+      - name: Install ESP32 platform dependencies
+        if: matrix.board.type == 'esp32'
+        run: pip3 install pyserial
+
       - name: Compile examples
         uses: arduino/compile-sketches@main
         with: