docs: add trademarks information to the projects page (#4858)

Added trademark information to the projects page

---------

Co-authored-by: Copilot <175728472+Copilot@users.noreply.github.com>

Author: dylanb

doc/projects.md

@@ -1,10 +1,10 @@
-# Projects that use axe-core
+# Projects that use axe-core®
 
 Add your project/integration to this file and submit a pull request.
 
 ## Deque Projects
 
-1. [Axe DevTools](https://www.deque.com/axe/devtools/)
+1. [Axe® DevTools](https://www.deque.com/axe/devtools/)
 1. [Axe Auditor](https://www.deque.com/axe/auditor/)
 1. [Axe Monitor](https://www.deque.com/axe/monitor/)
 1. [Axe Chrome Extension](https://chrome.google.com/webstore/detail/axe/lhdoppojpmngadmnindnejefpokejbdd)
@@ -60,3 +60,5 @@ Add your project/integration to this file and submit a pull request.
 1. [Sitebulb](https://sitebulb.com/hints/accessibility/)
 1. [Webatool](https://github.com/balajihambeere/webatool)
 1. [A11y Audit Elixir](https://github.com/angelikatyborska/a11y-audit-elixir)
+
+Axe® and axe-core® are registered trademarks of Deque Systems Inc.