Add test for interpolating byte strings in hook plugin
Add test for interpolating byte strings in hook plugin

SusannaMaria/beets,sampsyo/beets,shamangeorge/beets,beetbox/beets,ibmibmibm/beets,jackwilsdon/beets,SusannaMaria/beets,shamangeorge/beets,jackwilsdon/beets,sampsyo/beets,SusannaMaria/beets,jackwilsdon/beets,ibmibmibm/beets,beetbox/beets,beetbox/beets,sampsyo/beets,jackwilsdon/beets,ibmibmibm/beets,sampsyo/beets,shamangeorge/beets,shamangeorge/beets,SusannaMaria/beets,ibmibmibm/beets,beetbox/beets