fix: update javascript-node-postgres test db host from localhost to db

Update the PostgreSQL connection host in test/javascript-node-postgres/server.js
from 'localhost' to 'db' to match the bridge network configuration change
in docker-compose.yml.

Co-authored-by: Kaniska244 <[email protected]>

Author: Copilot

test/javascript-node-postgres/server.js

@@ -12,7 +12,7 @@ const promise = require('bluebird');
 const PORT = 3000;
 const HOST = '0.0.0.0';
 const cn = {
-	host: 'localhost', // host of db container
+	host: 'db', // host of db container
 	port: 5432, // 5432 is the default;
 	database: 'postgres', // database name
 	user: 'postgres', // database user name