Fill in release date for 5.2.8

CHANGELOG.txt

@@ -1,7 +1,7 @@
 Changelog
 =========
 
-5.2.8 (xx.xx.xxxx) - IN DEVELOPMENT
+5.2.8 (03.02.2025)
 ~~~~~~~~~~~~~~~~~~
 
  * Fix: Prevent database error when calling permission_order.register on app ready (Daniel Kirkham, Matt Westcott)

docs/releases/5.2.8.md

@@ -1,6 +1,6 @@
 # Wagtail 5.2.8 release notes
 
-_Unreleased_
+_February 3, 2025_
 
 ```{contents}
 ---