api/service-patterns/tiktok: allow longer shortLink

tiktok is a/b testing a new shortLink format that's ±19 characters long but behaves the same way as old format

Author: wukko

api/src/processing/service-patterns.js

@@ -43,7 +43,7 @@ export const testers = {
         pattern.id?.length <= 6,
 
     "tiktok": pattern =>
-        pattern.postId?.length <= 21 || pattern.shortLink?.length <= 13,
+        pattern.postId?.length <= 21 || pattern.shortLink?.length <= 21,
 
     "tumblr": pattern =>
         pattern.id?.length < 21