Following up on our recent extension outage, this PR adds an action to
quickly visit our status page (which with the help of @\gaauwe was
recently updated to a more up to date design 🎉 ).

While already invokable through the command palette, we can later use
this to also add buttons where appropriate for a quick lookup of our
current status.

Release Notes:

- Added the `zed::OpenStatusPage` action to be able to easily visit the
Zed status page.