Missing default DB_POOL value

README.md

@@ -34,6 +34,7 @@ the list of what you can use:
 - `TOOTCTL`, string, path to tootctl binary, default: 
 `/home/mastodon/live/bin/tootctl`
 - `DB_POOL`, integer, concurrency to use (connections to PostgreSQL), default: 
+`5`
 - `DRY_RUN`, boolean, run or not in dry-run mode, default: `true`
 - `TLS_EXPIRED_MAX_SEC`, integer, number of seconds, age difference between now 
 and date of expired certificate, default: `1210000`, 2w