Upgrade to Wagtail 4

requirements/base.txt

@@ -1,5 +1,5 @@
 Django>=4.0,<4.1
 django-dotenv==1.4.1
-wagtail>=3.0,<4
+wagtail>=4.0,<5
 wagtailfontawesome>=1.1.3,<1.2
 django-debug-toolbar>=3.2,<4