[OTA] Enable 2 clicks OTA update / one simple MQTT command (#1485)

* [OTA] Add automatic OTA updates

This feature will enable to update the gateway with one button or a simple MQTT command.

* [CI] Enable automatic OTA for nightly development builds

And integrate the latest_version file creation into the CI

Enable to specify a particular version
and switch between dev and production builds

.github/workflows/build_and_docs_to_dev.yml

@@ -25,11 +25,13 @@ jobs:
           npm install
       - name: Set sha tag
         run: |
-          sed -i "s/version_tag/${{ steps.short-sha.outputs.sha }}/g" main/User_config.h
+          sed -i "s/version_tag/${{ steps.short-sha.outputs.sha }}/g" main/User_config.h scripts/latest_version_dev.json
           sed -i "s/version_tag/DEVELOPMENT SHA:${{ steps.short-sha.outputs.sha }} TEST ONLY/g" docs/.vuepress/config.js
           sed -i "s|base: '/'|base: '/dev/'|g" docs/.vuepress/config.js
       - name: Run PlatformIO
-        run: platformio run
+        run: |
+          export PLATFORMIO_BUILD_FLAGS="'-DDEVELOPMENTOTA=true'"
+          platformio run
       - name: Prepare Release Assets
         run: |
           sudo apt install rename