Adds esp_mqtt_cxx component

- Component moved from esp-idf
- Files moved to adjust to esp-protocol structure

.github/workflows/target-test.yml

@@ -179,6 +179,27 @@ jobs:
             ${{ env.TEST_DIR }}/build/config/sdkconfig.json
           if-no-files-found: error
 
+  build_esp_mqtt_cxx:
+      strategy:
+        matrix:
+          idf_ver: ["latest", "release-v5.0"]
+          idf_target: ["esp32"]
+          test: [ { app: example, path: "components/esp_mqtt_cxx/examples" }]
+      runs-on: ubuntu-20.04
+      container: espressif/idf:${{ matrix.idf_ver }}
+      steps:
+        - name: Checkout esp-protocols
+          uses: actions/checkout@v3
+          with:
+            submodules: recursive
+        - name: Build ${{ matrix.test.app }} with IDF-${{ matrix.idf_ver }} for ${{ matrix.idf_target }}
+          shell: bash
+          working-directory: ${{matrix.test.path}}
+          run: |
+            ${IDF_PATH}/install.sh --enable-pytest
+            . ${IDF_PATH}/export.sh
+            python $IDF_PATH/tools/ci/ci_build_apps.py . --target ${{ matrix.idf_target }} -vv --preserve-all --pytest-app
+
   run-target-websocket:
     name: Run Websocket Example Test on target
     needs: build_websocket