fix(lib/db): type mismatch (#23107)

Fixes "Type 'string' is not assignable to type 'number'." TS warning

examples/with-mysql/lib/db.ts

@@ -6,7 +6,7 @@ export const db = mysql({
     database: process.env.MYSQL_DATABASE,
     user: process.env.MYSQL_USERNAME,
     password: process.env.MYSQL_PASSWORD,
-    port: process.env.MYSQL_PORT,
+    port: parseInt(process.env.MYSQL_PORT),
   },
 })