Update changelog

CHANGELOG.md

@@ -2,6 +2,7 @@
 
 ## [Unreleased](https://github.com/pixelfed/pixelfed/compare/v0.10.7...dev)
 ### Added
+- Added ```BANNED_USERNAMES``` .env var, an optional comma separated string to ban specific usernames from being used ([6cdd64c6](https://github.com/pixelfed/pixelfed/commit/6cdd64c6))
 
 ### Fixed
 - Fixed Story Compose bug affecting postgres instances ([#1918](https://github.com/pixelfed/pixelfed/pull/1918))