Pipeline to update Mautic

[froger]

• pipeline to update community.mautic.org with a manual action on a tag.
• pipeline to update a test instance manually (from main).
• update docker hub config (@RCheesley)

[RCheesley]

I've updated the Dockerhub so it now triggers on either pushes to main (which builds as latest) or pushes to tags.

[froger]

@RCheesley we have now a manual workflow, with two environments Production or Development.
https://github.com/mautic/Community-Portal/actions/workflows/redeploy-dev.yml

When triggering the workflow, you will be ask in which environment you want to redeploy the docker image.
The redeploy process takes around 2min, and the instance will be down for a 5min-ish duration.

This has been tested on development. I can see now there is some issue on a fresh redeploy, that I am fixing right now.

There is now issues on a fresh re-deploy, that I described here: #66, so my side you can close this issue 🎉🎉🎉

[RCheesley]

That's super awesome! Thanks for setting this up!