Fixed identifier word

Changed an an to a the.

doc/settings/database.md

@@ -200,7 +200,7 @@ can use this.
    }
    ```
-   Set `listen_address` as an IP address of the server that the clients will use
+   Set `listen_address` as the IP address of the server that the clients will use
    to connect to the database.
    Ensure `cert_auth_addresses` contains a list of IP addresses, and the
    databases and users that are allowed to connect to the database. You can use