Change last_updated_at to dateTime

Signed-off-by: iris <hellocomplex007@gmail.com>

plugins/catalog-backend/migrations/20221201085245_add_last_updated_at_in_final_entities.js

@@ -17,7 +17,7 @@
 exports.up = async function up(knex) {
   await knex.schema.table('final_entities', table => {
     table
-      .bigint('last_updated_at')
+      .dateTime('last_updated_at')
       .nullable()
       .comment('The time when final_entity changed');
   });

plugins/catalog-backend/src/database/tables.ts

@@ -66,7 +66,7 @@ export type DbFinalEntitiesRow = {
   hash: string;
   stitch_ticket: string;
   final_entity?: string;
-  last_updated_at: string | null;
+  last_updated_at: string | Date;
 };
 
 export type DbSearchRow = {

plugins/catalog-backend/src/stitching/Stitcher.ts

@@ -23,7 +23,6 @@ import {
 import { SerializedError, stringifyError } from '@backstage/errors';
 import { Knex } from 'knex';
 import { v4 as uuid } from 'uuid';
-import { DateTime } from 'luxon';
 import { Logger } from 'winston';
 import {
   DbFinalEntitiesRow,
@@ -208,12 +207,12 @@ export class Stitcher {
       .update({
         final_entity: JSON.stringify(entity),
         hash,
-        last_updated_at: `${DateTime.now().toMillis()}`,
+        last_updated_at: this.database.fn.now(),
       })
       .where('entity_id', entityId)
       .where('stitch_ticket', ticket)
       .onConflict('entity_id')
-      .merge(['final_entity', 'hash']);
+      .merge(['final_entity', 'hash', 'last_updated_at']);
 
     if (amountOfRowsChanged === 0) {
       this.logger.debug(