[CI] Add github-pat to trivy-scan.yml

Adds Github token to the trivy scan in an effort to prevent the
recent CI failures due to TOOMANYREQUESTS on downloading the Trivy
db.

(cherry picked from commit 3ad7235a87)

.github/workflows/trivy-scan.yml

@@ -44,6 +44,7 @@ jobs:
           scan-type: 'fs'
           scan-ref: '${{ env.LOCAL_REPOSITORY_PATH }}/org/springframework/pulsar'
           trivy-config: ${{ inputs.config-path }}
+          github-pat: ${{ secrets.GH_ACTIONS_REPO_TOKEN }}
       - name: Upload Trivy scan results to GitHub Security tab
         if: inputs.upload-results
         uses: github/codeql-action/upload-sarif@v3