Fix typo in project-structure.md (brianc#3008)

Author: thearian

docs/pages/guides/project-structure.md

@@ -44,7 +44,7 @@ That's it. But now everywhere else in my application instead of requiring `pg` d
 import * as db from '../db.js'
 
 app.get('/:id', async (req, res, next) => {
-  const result = await db.query('SELECT * FROM users WHERE id = $1', [req.params.id]
+  const result = await db.query('SELECT * FROM users WHERE id = $1', [req.params.id])
   res.send(result.rows[0])
 })