feat: Introduce position to step model

packages/backend/src/db/migrations/20220127141941_add_position_to_steps.ts

@@ -0,0 +1,13 @@
+import { Knex } from 'knex';
+
+export async function up(knex: Knex): Promise<void> {
+  return knex.schema.table('steps', (table) => {
+    table.integer('position').notNullable();
+  });
+}
+
+export async function down(knex: Knex): Promise<void> {
+  return knex.schema.table('steps', (table) => {
+    table.dropColumn('position');
+  });
+}