feat: add owner index to subdomains table (#1331)

* feat: add owner index to subdomains table

* chore: move to separate migration

src/migrations/1663701407339_subdomains_owner_index.ts

@@ -0,0 +1,8 @@
+/* eslint-disable @typescript-eslint/camelcase */
+import { MigrationBuilder, ColumnDefinitions } from 'node-pg-migrate';
+
+export const shorthands: ColumnDefinitions | undefined = undefined;
+
+export async function up(pgm: MigrationBuilder): Promise<void> {
+  pgm.createIndex('subdomains', 'owner');
+}