use get-pr-info from nv-gha-runners (#16819)

There are two implementations of the same action; one in
[rapidsai/shared-actions](https://github.com/rapidsai/shared-actions/tree/main/get-pr-info)
and [the other](https://github.com/nv-gha-runners/get-pr-info) in the
nv-gha-runners org. This PR switches to the implementation in the
nv-gha-runners group in order to keep a single source of truth.

Tested in
https://github.com/rapidsai/cudf/actions/runs/10906617425/job/30268277178?pr=16819#step:4:5

.github/workflows/pr.yaml

@@ -52,7 +52,7 @@ jobs:
     steps:
       - name: Get PR info
         id: get-pr-info
-        uses: rapidsai/shared-actions/get-pr-info@main
+        uses: nv-gha-runners/get-pr-info@main
       - name: Checkout code repo
         uses: actions/checkout@v4
         with: