quick follow for #2940: skip max queue limit check if limit is 0

Author: ikreymer

backend/btrixcloud/crawlconfigs.py

@@ -1228,7 +1228,7 @@ async def check_if_too_many_waiting_crawls(self, org: Organization):
         """if max concurrent crawls are set, limit number of queued crawls to X concurrent limit
         return 429 if at limit"""
         max_concur = org.quotas.maxConcurrentCrawls
-        if not max_concur:
+        if not max_concur or not self.crawl_queue_limit_scale:
             return
 
         num_waiting = await self.crawls.count_documents(