Make the dashboard page titles more descriptive

[AtkinsSJ]

While browsing tests to try and fix them in Ladybird, I often end up with several tabs open on wpt.fyi. It would be helpful to me to distinguish them if they didn't all just say "web-platform-tests dashboard" in the title, but instead said which page you're viewing.

For example:

• https://wpt.fyi/results/css -> "css | web-platform-tests dashboard"
• https://wpt.fyi/results/css/css-images/parsing/gradient-interpolation-method-valid.html -> "css/css-images/parsing/gradient-interpolation-method-valid.html | web-platform-tests dashboard" - Or perhaps just "gradient-interpolation-method-valid.html | web-platform-tests dashboard"

Maybe even shorten the name so it's not "things | web-platform-tests dashboard" but just "things | WPT.fyi".

A lot of configuration ends up in the URL for which versions of which browsers to show, which might be useful to also include, but it's less clear to me how to do that without it being unwieldy. (Maybe "things (Ch/FF/Ed) | WPT.fyi" or some other abbreviations?) To me at least, the path would be very useful to include, and anything else less so.