fix: remove head commit checkout to instead use merge commit for docs-link… (#3840)

Signed-off-by: Nate Mailhot <nmailhot@nvidia.com>

.github/workflows/docs-link-check.yml

@@ -15,11 +15,6 @@ jobs:
     steps:
       - name: Check out repository
         uses: actions/checkout@v4
-        with:
-          # For pull_request events, use the PR head (commit from the contributor's branch/repo)
-          repository: ${{ github.event.pull_request.head.repo.full_name || github.repository }}
-          ref: ${{ github.event.pull_request.head.sha || github.sha }}
-          fetch-depth: 0
 
       # Cache lychee results (e.g. to avoid hitting rate limits)
       # https://lychee.cli.rs/github_action_recipes/caching/