Fix average rating where likes and dislikes are null

src/invidious/videos.cr

@@ -649,7 +649,9 @@ def fetch_video(id, proxies, region)
   dislikes = dislikes.try &.content.delete(",").try &.to_i?
   dislikes ||= 0
 
-  info["avg_rating"] = "#{(likes.to_f/(likes.to_f + dislikes.to_f) * 4 + 1)}"
+  avg_rating = (likes.to_f/(likes.to_f + dislikes.to_f) * 4 + 1)
+  avg_rating = avg_rating.nan? ? 0.0 : avg_rating
+  info["avg_rating"] = "#{avg_rating}"
 
   description = html.xpath_node(%q(//p[@id="eow-description"]))
   description = description ? description.to_xml : ""