ci: update the security-scanner gha token

Author: dduzgun-security

.github/workflows/security-scan.yml

@@ -59,7 +59,7 @@ jobs:
         uses: actions/checkout@692973e3d937129bcbf40652eb9f2f61becf3332 # v4.1.7
         with:
           repository: hashicorp/security-scanner
-          token: ${{ secrets.HASHIBOT_PRODSEC_GITHUB_TOKEN }}
+          token: ${{ secrets.PRODSEC_SCANNER_READ_ONLY }}
           path: security-scanner
           ref: main