streams: Remove is_in_zephyr_realm field from database.

Signed-off-by: Anders Kaseorg <anders@zulip.com>

zerver/migrations/0752_remove_stream_is_in_zephyr_realm.py

@@ -0,0 +1,16 @@
+# Generated by Django 5.2.6 on 2025-09-08 21:01
+
+from django.db import migrations
+
+
+class Migration(migrations.Migration):
+    dependencies = [
+        ("zerver", "0751_externalauthid_zerver_user_externalauth_uniq"),
+    ]
+
+    operations = [
+        migrations.RemoveField(
+            model_name="stream",
+            name="is_in_zephyr_realm",
+        ),
+    ]