chore(commits): Remove unused dual write commit tables (#102504)

We're no longer planning on using the dual written tables, so removing
these tables. This is the first step, where we remove them from the
codebase.

<!-- Describe your PR here. -->

Author: wedamija

migrations_lockfile.txt

@@ -27,7 +27,7 @@ preprod: 0018_add_preprod_artifact_app_icon_id_field
 
 prevent: 0002_alter_integration_id_not_null
 
-releases: 0001_release_models
+releases: 0002_delete_dual_written_commit_tables
 
 replays: 0006_add_bulk_delete_job
 

src/sentry/releases/migrations/0002_delete_dual_written_commit_tables.py

@@ -0,0 +1,55 @@
+# Generated by Django 5.2.1 on 2025-10-31 19:01
+
+import django.db.models.deletion
+from django.db import migrations
+
+import sentry.db.models.fields.foreignkey
+from sentry.new_migrations.migrations import CheckedMigration
+from sentry.new_migrations.monkey.models import SafeDeleteModel
+from sentry.new_migrations.monkey.state import DeletionAction
+
+
+class Migration(CheckedMigration):
+    # This flag is used to mark that a migration shouldn't be automatically run in production.
+    # This should only be used for operations where it's safe to run the migration after your
+    # code has deployed. So this should not be used for most operations that alter the schema
+    # of a table.
+    # Here are some things that make sense to mark as post deployment:
+    # - Large data migrations. Typically we want these to be run manually so that they can be
+    #   monitored and not block the deploy for a long period of time while they run.
+    # - Adding indexes to large tables. Since this can take a long time, we'd generally prefer to
+    #   run this outside deployments so that we don't block them. Note that while adding an index
+    #   is a schema change, it's completely safe to run the operation after the code has deployed.
+    # Once deployed, run these manually via: https://develop.sentry.dev/database-migrations/#migration-deployment
+
+    is_post_deployment = False
+
+    dependencies = [
+        ("releases", "0001_release_models"),
+        ("sentry", "1001_prevent_grouphistory_infinte_recursion"),
+    ]
+
+    operations = [
+        migrations.AlterField(
+            model_name="commit",
+            name="author",
+            field=sentry.db.models.fields.foreignkey.FlexibleForeignKey(
+                db_constraint=False,
+                null=True,
+                on_delete=django.db.models.deletion.CASCADE,
+                related_name="releasecommit_set",
+                to="sentry.commitauthor",
+            ),
+        ),
+        migrations.AlterField(
+            model_name="commitfilechange",
+            name="commit",
+            field=sentry.db.models.fields.foreignkey.FlexibleForeignKey(
+                db_constraint=False,
+                on_delete=django.db.models.deletion.CASCADE,
+                to="releases.commit",
+            ),
+        ),
+        SafeDeleteModel(name="Commit", deletion_action=DeletionAction.MOVE_TO_PENDING),
+        SafeDeleteModel(name="CommitFileChange", deletion_action=DeletionAction.MOVE_TO_PENDING),
+    ]