Fixed #36652 -- Increased determinism when loading migrations from disk.

Ordering still depends on pkgutil.iter_modules, which does not guarantee
order, but at least now Django is not introducing additional indeterminism,
causing CircularDependencyError to appear or not appear in some edge cases.

Co-authored-by: Jacob Walls <jacobtylerwalls@gmail.com>

tests/migrations/test_migrations_squashed_replaced_order/app1/0001_initial.py

@@ -0,0 +1,9 @@
+from django.db import migrations
+
+
+class Migration(migrations.Migration):
+    initial = True
+
+    dependencies = []
+
+    operations = []

tests/migrations/test_migrations_squashed_replaced_order/app1/0001_squashed_initial.py

@@ -0,0 +1,13 @@
+from django.db import migrations
+
+
+class Migration(migrations.Migration):
+    initial = True
+
+    replaces = [
+        ("app1", "0001_initial"),
+    ]
+
+    dependencies = []
+
+    operations = []

tests/migrations/test_migrations_squashed_replaced_order/app1/0002_squashed_initial.py

@@ -0,0 +1,16 @@
+from django.db import migrations
+
+
+class Migration(migrations.Migration):
+    initial = True
+
+    replaces = [
+        ("app1", "0001_initial"),
+    ]
+
+    dependencies = [
+        ("app1", "0001_squashed_initial"),
+        ("app2", "0001_squashed_initial"),
+    ]
+
+    operations = []

tests/migrations/test_migrations_squashed_replaced_order/app2/0001_initial.py

@@ -0,0 +1,11 @@
+from django.db import migrations
+
+
+class Migration(migrations.Migration):
+    initial = True
+
+    dependencies = [
+        ("app1", "0001_initial"),
+    ]
+
+    operations = []

tests/migrations/test_migrations_squashed_replaced_order/app2/0001_squashed_initial.py

@@ -0,0 +1,13 @@
+from django.db import migrations
+
+
+class Migration(migrations.Migration):
+    initial = True
+
+    replaces = [
+        ("app2", "0001_initial"),
+    ]
+
+    dependencies = []
+
+    operations = []