Closes #1050: Use correct (HTTPS) link for Passbolt, clarify tech used.

This commit updates the Passbolt entry so that it reads more clearly.
The programming language is already listed at the end of the entry, and
so there's no need to repeat it in the description. However, the
database backend (MySQL) should be noted in a grammatically clear way.

README.md

@@ -921,7 +921,7 @@ See https://github.com/n1trux/awesome-sysadmin#monitoring and https://github.com
 
 - [Bitwarden](https://bitwarden.com/) - Password manager with webapp, browser extension, and mobile app. ([Source Code](https://github.com/bitwarden/core)) `AGPL-3.0` `C#`
 - [keeweb](https://keeweb.info/) - This webapp is a browser and desktop password manager compatible with KeePass databases. ([Source Code](https://github.com/keeweb/keeweb)) `MIT` `HTML5`
-- [Passbolt](http://passbolt.com/) - Password manager dedicated for managing passwords in a collaborative way on any web server, MySQL and PHP. ([Source Code](https://github.com/passbolt/passbolt_api)) `AGPL-3.0` `PHP`
+- [Passbolt](https://www.passbolt.com/) - Password manager dedicated for managing passwords in a collaborative way on any Web server, using a MySQL database backend. ([Source Code](https://github.com/passbolt/passbolt_api)) `AGPL-3.0` `PHP`
 - [sysPass](http://www.syspass.org/) - Multiuser password management system. ([Demo](http://demo.syspass.org/), [Source Code](https://github.com/nuxsmin/sysPass)) `GPL-3.0` `PHP`
 - [Teampass](http://teampass.net/) - Password manager dedicated for managing passwords in a collaborative way on any server Apache, MySQL and PHP. ([Source Code](https://github.com/nilsteampassnet/TeamPass/)) `GPL-3.0` `PHP`