tests: Add test for episode resolution with URLs

When passing a GrlMedia without a title, make sure to get the basename
of the URL, and unescape it before trying to manipulate it.

file:///home/test/My%20super%20series.S01E01.mp4
should give:
My super series
as the show name, not:
My%20super%20series

https://bugzilla.gnome.org/show_bug.cgi?id=725456
local-metadata: Fix %20 in deduced titles

When passing a GrlMedia without a title, make sure to get the basename
of the URL, and unescape it before trying to manipulate it.

https://bugzilla.gnome.org/show_bug.cgi?id=725456