Remove a sentence from SECURITY.md

b/c that served as hint to developer (myself) when writing this
file and shouldn't have been left here.

Author: atodorov

SECURITY.md

@@ -2,9 +2,6 @@
 
 ## Supported Versions
 
-Use this section to tell people about which versions of your project are
-currently being supported with security updates.
-
 | Version | Supported          |
 | ------- | ------------------ |
 | [latest](https://pypi.org/project/pylint-django/) | :heavy_check_mark: |