Add versioning as action with mike

[GeertvanGeest]

@joseale2310 mentioned in #3: there is a tool that allows deployment of different versions of the webpage: https://github.com/jimporter/mike
Find an example here: https://squidfunk.github.io/mkdocs-material-example-versioning/0.3/

Possible solution:
Using mike is pretty powerful; we use it all the time for SIB courses (e.g. https://sib-swiss.github.io/single-cell-training/2023.3/). However, I never got to it to write an action that runs after a git tag (= a gh release) is given and pushes a new version with mike. Would be nice to have one.

[mihai-sysbio]

A side note: the issue description sounds very technical. It would be great if it could be expanded to include what value it would bring to the users of the template.

Another aspect to consider is what happens if/when the action breaks down. Since the action runs in each individual repository, it's hard to be aware of such failures and then to be able to go in and fix them. One idea would be to include a status update to a central location on the status of the build and some additional debugging information.