🐛 Fix RemovedInDjango60Warning for CheckConstraint in migration

Use a version-conditional kwarg in migration 0003 to pass `condition=`
on Django >= 5.1 and `check=` on Django 4.2, resolving the deprecation
warning without breaking backwards compatibility.

Author: swrichards

simple_certmanager/migrations/0003_signingrequest_and_more.py

@@ -82,7 +82,7 @@ class Migration(migrations.Migration):
         migrations.AddConstraint(
             model_name="signingrequest",
             constraint=models.CheckConstraint(
-                check=models.Q(
+                condition=models.Q(
                     models.Q(
                         models.Q(("csr", ""), ("private_key", "")),
                         models.Q(