Minor update to documentation for MySQL sessions

docs/sources/installation/configuration.md

@@ -327,7 +327,7 @@ This option should be configured differently depending on what type of
 session provider you have configured.
 session provider you have configured.
 
 
 - **file:** session file path, e.g. `data/sessions`
 - **file:** session file path, e.g. `data/sessions`
-- **mysql:** go-sql-driver/mysql dsn config string, e.g. `user:password@tcp(127.0.0.1)/database_name`
+- **mysql:** go-sql-driver/mysql dsn config string, e.g. `user:password@tcp(127.0.0.1:3306)/database_name`
 - **postgres:** ex:  user=a password=b host=localhost port=5432 dbname=c sslmode=disable
 - **postgres:** ex:  user=a password=b host=localhost port=5432 dbname=c sslmode=disable
 
 
 If you use MySQL or Postgres as the session store you need to create the
 If you use MySQL or Postgres as the session store you need to create the