Fixes#8071 and fixes https://github.com/certbot/certbot/issues/8110.
This PR migrates every job from Travis in Azure Pipeline.
This PR essentially converts the Travis jobs into Azure Pipeline with a complete iso-fonctionality (or I made a mistake). The jobs are added in the relevant existing pipelines (`main`, `nightly`, `advanced-test`, `release`). A global refactoring thanks to the templating system is done to reduce greatly the verbosity of the pipeline descriptions.
A specific feature (not present in Travis) is added: the stage `On_Failure`. Using directly the Mattermost API, it allows to notify pipeline failure in a Mattermost channel with a link to the failed pipelines without the need to authenticate to Microsoft.
See https://github.com/certbot/certbot/pull/8098#issuecomment-649873641 for the post merge actions to do at the end of this work.
I want to do what I did in https://github.com/certbot/certbot/pull/7733 to our Azure Pipelines setup, but unfortunately this isn't currently possible. The only filters available for service hooks for the "build completed" trigger are the pipeline and build status. See
To accomplish this, I propose splitting the "advanced" pipeline into two cases. One is for builds on protected branches where we want to be notified if they fail while the other is just used to manually run tests on certain branches.
