Fixed #23790 -- Warned about renaming AppConfig.label in docs/ref/applications.txt.

AUTHORS

@@ -87,6 +87,7 @@ answer newbie questions, and generally made Django that much better:
     Andrew Clark <amclark7@gmail.com>
     Andrew Durdin <adurdin@gmail.com>
     Andrew Godwin <andrew@aeracode.org>
+    Andrew Miller <info+django@akmiller.co.uk>
     Andrew Pinkham <http://AndrewsForge.com>
     Andrews Medina <andrewsmedina@gmail.com>
     Andrew Northall <andrew@northall.me.uk>

docs/ref/applications.txt

@@ -186,6 +186,14 @@ Configurable attributes
 
     It must be unique across a Django project.
 
+    .. warning::
+
+        Changing this attribute after migrations have been applied for an
+        application will result in breaking changes to a project or, in the
+        case of a reusable app, any existing installs of that app. This is
+        because ``AppConfig.label`` is used in database tables and migration
+        files when referencing an app in the dependencies list.
+
 .. attribute:: AppConfig.verbose_name
 
     Human-readable name for the application, e.g. "Administration".