check-nightly-ci: remove testing config (#2960)

Follow-up to #2956 

Removes some testing configuration left behind in that PR.

Authors:
  - James Lamb (https://github.com/jameslamb)

Approvers:
  - Kyle Edwards (https://github.com/KyleFromNVIDIA)

URL: #2960

Author: jameslamb

.github/workflows/pr.yaml

@@ -48,7 +48,6 @@ jobs:
       id-token: write
     env:
       GH_TOKEN: ${{ github.token }}
-      SHARED_ACTIONS_REF: 'check-nightly-success'
     steps:
       - name: Get PR Info
         id: get-pr-info