Fixed #31410 -- Added system checks for invalid model field names in UniqueConstraint.

django/db/models/base.py

@@ -1926,6 +1926,12 @@ class Model(metaclass=ModelBase):
                         id='models.W038',
                     )
                 )
+            fields = (
+                field
+                for constraint in cls._meta.constraints if isinstance(constraint, UniqueConstraint)
+                for field in constraint.fields
+            )
+            errors.extend(cls._check_local_fields(fields, 'constraints'))
         return errors