enable query profiling for debug

Author: ro0NL

doctrine/doctrine-bundle/1.12/config/packages/doctrine.yaml

@@ -1,6 +1,7 @@
 doctrine:
     dbal:
         url: '%env(resolve:DATABASE_URL)%'
+        profiling_collect_backtrace: '%kernel.debug%'
 
         # IMPORTANT: You MUST configure your server version,
         # either here or in the DATABASE_URL env var (see .env file)