filter out null entries in list

list can appear in the form:
```
[null, null {...}]
```
when anilist api does not return `episodeCount` number of episodes.

In the case of One Piece (ThaUnknown#568), only ep. 1122 is returned from the api,
leaving 1121 null's in the list before the first entry with actual
episode data

Author: 2547techno

common/views/ViewAnime/EpisodeList.svelte

@@ -58,7 +58,7 @@
   const animeProgress = liveAnimeProgress(id)
 </script>
 
-{#each episodeOrder ? episodeList : [...episodeList].reverse() as { episode, image, summary, rating, title, length, airdate, filler }}
+{#each episodeOrder ? episodeList.filter(e => e) : [...episodeList].reverse().filter(e => e) as { episode, image, summary, rating, title, length, airdate, filler }}
   {@const completed = !watched && userProgress >= episode}
   {@const target = userProgress + 1 === episode}
   {@const progress = !watched && ($animeProgress?.[episode] ?? 0)}