Update pnpm to v10.28.2

Author: renovate[bot]

package.json

@@ -2,7 +2,7 @@
   "name": "opensaas-stack",
   "version": "0.1.0",
   "private": true,
-  "packageManager": "pnpm@10.26.2",
+  "packageManager": "pnpm@10.28.2",
   "description": "A modern stack for building admin-heavy applications with Next.js App Router",
   "scripts": {
     "build": " pnpm turbo build",