Support apps with custom label.

tests/test_project/app_with_custom_name/models.py

@@ -0,0 +1,8 @@
+from __future__ import annotations
+
+from django.db import models
+
+
+class A(models.Model):
+    int_field = models.IntegerField()
+    char_field = models.CharField(max_length=255)