The event popover contains a lot of text in different sizes, which
pushes us to magic-number the maximum amount of characters
(i.e. `max-width-chars`) and hope that all is well.
This approach addresses that by simply clamping the parent widget
to the desired size, allowing us to remove all instances
of `max-width-chars`.
Do note that `Adw.Clamp:tightening-threshold` is set to 400 by default,
which technically doesn't need to bind to `Adw.Clamp:maximum-size` at
the moment, but I decided to do it anyway in case we want to change
`Adw.Clamp:maximum-size` in the future and can't figure out why
the margins are off.
Co-authored-by: Jamie Gravendeel <me@jamie.garden>
Part-of: <https://gitlab.gnome.org/GNOME/gnome-calendar/-/merge_requests/728>