In stable, the storyboard filename is fixed. In lazer, we were always
looking for the first `.osb` in the database. In the case a beatmap
archive housed more than one `.osb` files, this may load the incorrect
one.
Using `GetDisplayString` here feels like it could potentially go wrong
in the future, so I'm open to hard-coding this locally (or using string
manipulation to remove the ` [creator_name]` portion of the beatmap's
filename). Open to opinions on that.
Fixes storyboard playback in https://osu.ppy.sh/beatmapsets/1913687#osu/3947758
d15f8c2f3a