Adds continuous deployment to the "Latest Docker Image" workflow

[carloshellin]

1. Enable the webhook of this container at https://deploy.propamap.cc.uah.es/
2. Create a secret in this repo called WEBHOOK_URL (if you don't have permissions, reply in this issue with the URL and I'll create it)
3. Add the deploy job after build in the "Latest Docker Image CI" worflow. Use this code as an example:

   deploy:
     runs-on: ubuntu-latest
     needs: build
     steps:
     - name: Invoke deployment hook
       uses: joelwmale/webhook-action@master
       with:
         url: ${{ secrets.WEBHOOK_URL }}?tag=latest
         insecure: true

4. Check that it works. Every time a push is made to the main, the image of a container should be created and that image should automatically be deployed in the container at https://deploy.propamap.cc.uah.es/.

[carloshellin]

Generate a new webhook again and send it to me privately. At the next meeting I will explain why this now.

[carloshellin]

Generate a new webhook again and send it to me privately. At the next meeting I will explain why this now.

Done