Remove date in changelog.md

Author: bavalpey

changelog.md

@@ -3,7 +3,6 @@
 ## Unreleased
 <!-- Add all new changes here. They will be moved under a version at release -->
 * `NEW` Add postfix snippet for `unpack`
-`2024-6-19`
 * `NEW` Add support for lambda style functions, `|paramList| expr` is syntactic sugar for `function(paramList) return expr end` 
 
 ## 3.9.3