Update Postfix attachment_size how-to

docs/manual-guides/Postfix/u_e-postfix-attachment_size.en.md

@@ -1,14 +1,19 @@
 Open `data/conf/postfix/extra.cf` and set the `message_size_limit` accordingly in bytes. See `main.cf` for the default value.
 
-Restart Postfix:
+Also you need align message size in Rspamd and Clamav configurations:
+- in `data/conf/rspamd/local.d/options.inc` add `max_message` parameter, check [Rspamd Docs](https://rspamd.com/doc/configuration/options.html#:~:text=DoS%20(default%3A%201024)-,max_message,-maximum%20size%20of) for defaults
+- in `data/conf/clamav/clamd.conf` adjust `MaxScanSize` and `MaxFileSize`
+
+
+Restart Postfix, Rspamd and Clamav:
 === "docker compose (Plugin)"
 
     ``` bash
-    docker compose restart postfix-mailcow
+    docker compose restart postfix-mailcow rspamd-mailcow clamd-mailcow
     ```
 
 === "docker-compose (Standalone)"
 
     ``` bash
-    docker-compose restart postfix-mailcow
+    docker-compose restart postfix-mailcow rspamd-mailcow clamd-mailcow
     ```