ci: redistribute canonical secret-scanner.yml (concurrency-cancel guard) (Refs hyperpolymath/standards#122)

Author: hyperpolymath

.github/workflows/secret-scanner.yml

@@ -1,4 +1,4 @@
-# SPDX-License-Identifier: PMPL-1.0-or-later
+# SPDX-License-Identifier: PMPL-1.0
 # Prevention workflow - scans for hardcoded secrets before they reach main
 name: Secret Scanner
 
@@ -15,13 +15,14 @@ concurrency:
   group: ${{ github.workflow }}-${{ github.ref }}
   cancel-in-progress: true
 
-permissions: read-all
+permissions:
+  contents: read
 
 jobs:
   trufflehog:
     runs-on: ubuntu-latest
     steps:
-      - uses: actions/checkout@de0fac2e4500dabe0009e67214ff5f5447ce83dd # v6.0.2
+      - uses: actions/checkout@de0fac2e4500dabe0009e67214ff5f5447ce83dd # v4
         with:
           fetch-depth: 0  # Full history for scanning
 
@@ -35,7 +36,7 @@ jobs:
   gitleaks:
     runs-on: ubuntu-latest
     steps:
-      - uses: actions/checkout@de0fac2e4500dabe0009e67214ff5f5447ce83dd # v6.0.2
+      - uses: actions/checkout@de0fac2e4500dabe0009e67214ff5f5447ce83dd # v4
         with:
           fetch-depth: 0
 
@@ -48,7 +49,7 @@ jobs:
   rust-secrets:
     runs-on: ubuntu-latest
     steps:
-      - uses: actions/checkout@de0fac2e4500dabe0009e67214ff5f5447ce83dd # v6.0.2
+      - uses: actions/checkout@de0fac2e4500dabe0009e67214ff5f5447ce83dd # v4
 
       - name: Check for hardcoded secrets in Rust
         run: |