Mention email change in changelog

CHANGELOG.txt

@@ -46,6 +46,7 @@ Changelog
  * Added documentation for creating custom submenus in the admin menu (Sævar Öfjörð Magnússon)
  * Choice blocks in StreamField now show label rather than value when collapsed (Jérôme Lebleu)
  * Added documentation to clarify configuration of user-uploaded files (Cynthia Kiser)
+ * Change security contact address to security@wagtail.org (Jake Howard)
  * Fix: Accessibility fixes for Windows high contrast mode; Dashboard icons colour and contrast, help/error/warning blocks for fields and general content, side comment buttons within the page editor, dropdown buttons (Sakshi Uppoor, Shariq Jamil, LB (Ben Johnston), Jason Attwood)
  * Fix: Rename additional 'spin' CSS animations to avoid clashes with other libraries (Kevin Gutiérrez)
  * Fix: `default_app_config` deprecations for Django >= 3.2 (Tibor Leupold)

docs/releases/2.16.md

@@ -68,6 +68,7 @@ Thank you to [The National Archives](https://www.nationalarchives.gov.uk) for ki
  * Added documentation for creating custom submenus in the admin menu (Sævar Öfjörð Magnússon)
  * Choice blocks in StreamField now show label rather than value when collapsed (Jérôme Lebleu)
  * Added documentation to clarify configuration of user-uploaded files (Cynthia Kiser)
+ * Change security contact address to security@wagtail.org (Jake Howard)
 
 ### Bug fixes
 
@@ -81,6 +82,7 @@ Thank you to [The National Archives](https://www.nationalarchives.gov.uk) for ki
  * Ensure subsequent changes to styles files are picked up by Gulp watch (Jason Attwood)
  * Ensure that programmatic page moves are correctly logged as 'move' and not 'reorder' in some cases (Andy Babic)
 
+
 ## Upgrade considerations
 
 ### Removed support for Django 3.0 and 3.1