Add changelog for adding warning for unsaved edits in snippets

Closes #8453

CHANGELOG.txt

@@ -19,6 +19,7 @@ Changelog
  * Add support for Python 3.13 (Matt Westcott)
  * Fire `copy_for_translation_done` signal when copying translatable models as well as pages (Coen van der Kamp)
  * Add support for an image `description` field across all images, to better support accessible image descriptions (Chiemezuo Akujobi)
+ * Prompt the user about unsaved changes when editing snippets (Sage Abdullah)
  * Fix: Prevent page type business rules from blocking reordering of pages (Andy Babic, Sage Abdullah)
  * Fix: Improve layout of object permissions table (Sage Abdullah)
  * Fix: Fix typo in aria-label attribute of page explorer navigation link (Sébastien Corbin)

docs/releases/6.3.md

@@ -34,6 +34,7 @@ This release adds formal support for Django 5.1.
  * Consistently use `capfirst` for title-casing model verbose names (Sébastien Corbin)
  * Fire `copy_for_translation_done` signal when copying translatable models as well as pages (Coen van der Kamp)
  * Add support for an image `description` field across all images, to better support accessible image descriptions (Chiemezuo Akujobi)
+ * Prompt the user about unsaved changes when editing snippets (Sage Abdullah)
 
 ### Bug fixes