Remove the warning about Plesk not being supported on CL9

The support for Plesk has been recently announced.
See https://blog.cloudlinux.com/announcing-support-for-cloudlinux-9-with-plesk

Author: prilr

docs/cloudlinuxos/cloudlinux_installation/README.md

@@ -112,10 +112,6 @@ Supported control panels:
 * InterWorx ([Documentation](https://appendix.interworx.com/current/nodeworx/plugins/install-use-cloudlinux-plugin-interworx.html))
 * Webuzo ([Documentation](https://webuzo.com/docs/installing-webuzo/install-cloudlinux-os/))
 
-:::warning Warning:
-CloudLinux 9 does not support Plesk. 
-:::
-
 :::warning Other control panels:
 Control panels not mentioned in the list of supported panels have native integration or integration done by the developer of the panel.
 We cannot guarantee the stability or correct operation of CloudLinux components on such panels.