Bug 1840697 - Port bug 1839789: Migrate Thunderbird maintained Docker images to Debian 12. r=dandarnell

Bug 1839789 migrates build tasks; the mingw image falls under that category sort
of. The ATN upload image just do and get it out of the way.

Differential Revision: https://phabricator.services.mozilla.com/D182284

--HG--
extra : moz-landing-system : lando

taskcluster/ci/docker-image/docker-image.yml

@@ -5,11 +5,11 @@
 
 tb-debian-mingw:
     symbol: I(tb-mingw)
-    parent: debian11-amd64-build
+    parent: debian12-amd64-build
 
 thunderbird-flatpak:
     symbol: I(flatpak)
 
 tb-atn:
     symbol: I(tb-atn)
-    parent: debian11-base
+    parent: debian12-base