CHANGELOG has space for 4.0 release

Author: johnkary

CHANGELOG.md

@@ -5,7 +5,11 @@ View diff for a specific commit:
 https://github.com/johnkary/phpunit-speedtrap/commit/XXX where XXX is the commit hash
 
 View diff between two versions:  
-https://github.com/johnkary/phpunit-speedtrap/compare/v3.2.0...v3.3.0
+https://github.com/johnkary/phpunit-speedtrap/compare/v3.3.0...v4.0.0
+
+## 4.0 (xxxx-xx-xx)
+
+
 
 ## 3.3.0 (2020-12-18)