chore: downgrade @openedx/brand-openedx to ^1.2.3 (#3042)

Reverts the v2 bump from openedx/public-engineering#505 while keeping
the existing @edx/brand npm alias. Refs openedx/public-engineering#508.

Author: arbrandes

package-lock.json

@@ -43,7 +43,7 @@
     "@dnd-kit/modifiers": "^7.0.0",
     "@dnd-kit/sortable": "^8.0.0",
     "@dnd-kit/utilities": "^3.2.2",
-    "@edx/brand": "npm:@openedx/brand-openedx@^2.0.0",
+    "@edx/brand": "npm:@openedx/brand-openedx@^1.2.3",
     "@edx/browserslist-config": "1.5.1",
     "@edx/frontend-component-footer": "^14.9.0",
     "@edx/frontend-component-header": "^8.2.1",