chore(ci): update GitHub Actions workflow to use latest nx-set-shas version and improve event trigger format

Author: manudeli

.github/workflows/pr.yml

@@ -1,6 +1,7 @@
 name: pr
 
-on: [pull_request]
+on:
+  pull_request:
 
 concurrency:
   group: ${{ github.workflow }}-${{ github.event.number || github.ref }}
@@ -25,7 +26,7 @@ jobs:
       - name: Setup Tools
         uses: tanstack/config/.github/setup@main
       - name: Get base and head commits for `nx affected`
-        uses: nrwl/nx-set-shas@v4.1.2
+        uses: nrwl/nx-set-shas@v4.4.0
       - name: Run Tests
         run: pnpm run test:pr --parallel=3
       - name: Stop Agents