Remove version specification and installation flag for pnpm in GitHub Actions workflow, streamlining the setup process.

.github/workflows/validate-pr.yml

@@ -48,9 +48,6 @@ jobs:
 
       - uses: pnpm/action-setup@v4
         name: Install pnpm
-        with:
-          version: 8
-          run_install: false
 
       - name: Get pnpm store directory
         shell: bash