Bug 1946446 - Update about:rights r=geckoview-reviewers,desktop-theme-reviewers,fluent-reviewers,dao,flod,m_kato,sessionstore-reviewers,Gijs,nsharpley

- Redirect about:rights to terms page
  - Remove code related to old in-tree about:rights page

[[ https://mozilla-hub.atlassian.net/browse/FIDE-2485 | See Jira ticket ]]

Differential Revision: https://phabricator.services.mozilla.com/D237913

browser/tools/mozscreenshots/mozscreenshots/extension/configurations/ControlCenter.sys.mjs

@@ -32,7 +32,7 @@ export var ControlCenter = {
     about: {
       selectors: CC_SELECTORS,
       async applyConfig() {
-        await loadPage("about:rights");
+        await loadPage("about:policies");
         await openIdentityPopup();
       },
     },