Take down the old website

[surchs]

https://neurobagel.github.io/ is still reachable, although we have archived https://github.com/neurobagel/neurobagel.github.io earlier this year. The issue is that the domain is pretty memorable, and also the root-domain of our current development docs: https://neurobagel.github.io/dev-docs/ - so easy to get to.

Probably some folks also land on the old website via google 🤷

So my point is that we should:

• make sure make sure https://neurobagel.github.io/ either reroutes to our official docs or
• replace the contents of https://neurobagel.github.io/ with something else that also has a clear and visible link to the official website.