The format of the .desktop file names and their StartupWMClass of
Chromium and Chrome shortcuts has changed, so update the docs to match
the most recent versions of these web browsers.
The user interface to create shortcuts has also changed. They are no
longer created through a "Tools" menu (which doesn't exist anymore), but
rather through a "Save and share" menu. So add that to the docs as well.
Finally, replace the examples using the GNOME Wiki with examples using
the new GNOME Developer Handbook.
Closes: https://gitlab.gnome.org/GNOME/gnome-shell/-/issues/7482
Part-of: <https://gitlab.gnome.org/GNOME/gnome-shell/-/merge_requests/3289>
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