update iredmail source code URL (the bitbucket repository has been deleted)

README.md

@@ -326,7 +326,7 @@ _Simple deployment of a mail server, e.g. for inexperienced or impatient admins.
 - [docker-mailserver](https://github.com/tomav/docker-mailserver) - Fullstack but simple mail server (smtp, imap, antispam, antivirus, etc.). Only configuration files, no SQL database. Keep it simple and versioned. Easy to deploy and upgrade. `MIT` `Docker`
 - [Inboxen](https://inboxen.org) - Inboxen is a service that provides you with an infinite number of unique inboxes. ([Source Code](https://github.com/Inboxen/Inboxen)) `GPL-3.0` `Python`
 - [homebox](https://github.com/progmaticltd/homebox) - Suite of Ansible scripts to deploy a fully functional mail server on Debian. Unobtrusive and automatic as much as possible, focusing on stability and security. `GPL-3.0` `Shell`
-- [iRedMail](http://www.iredmail.org/) - Full-featured mail server solution based on Postfix and Dovecot. ([Source Code](https://bitbucket.org/zhb/iredmail/commits/)) `GPL-3.0` `Shell`
+- [iRedMail](http://www.iredmail.org/) - Full-featured mail server solution based on Postfix and Dovecot. ([Source Code](https://github.com/iredmail/iRedMail)) `GPL-3.0` `Shell`
 - [Mailcow](https://mailcow.email/) - Mail server suite based on Dovecot, Postfix and other open source software, that provides a modern Web UI for administration. ([Source Code](https://github.com/mailcow/mailcow-dockerized)) `GPL-2.0` `Docker/PHP`
 - [Mailu](https://mailu.io/) - Mailu is a simple yet full-featured mail server as a set of Docker images. ([Demo](https://github.com/Mailu/Mailu/wiki/Demo-server), [Source Code](https://github.com/Mailu/Mailu)) `MIT` `Docker/Python`
 - [Mail-in-a-Box](https://mailinabox.email/) - Turns any Ubuntu server into a fully functional mail server with one command. ([Source Code](https://github.com/mail-in-a-box/mailinabox)) `CC0-1.0` `Shell`