AlbumTrack: Fix is_track_present trigger

Which was created as is_track_presentAFTER, which apparently defaults to
a BEFORE trigger, causing the wrong is_present value to be used

src/AlbumTrack.cpp

@@ -111,7 +111,7 @@ void AlbumTrack::createTable( sqlite::Connection* dbConnection )
 
 void AlbumTrack::createTriggers(sqlite::Connection* dbConnection)
 {
-    const std::string triggerReq = "CREATE TRIGGER IF NOT EXISTS is_track_present"
+    const std::string triggerReq = "CREATE TRIGGER IF NOT EXISTS is_track_present "
             "AFTER UPDATE OF is_present "
             "ON " + policy::MediaTable::Name + " "
             "BEGIN "