feat: official Debian 11 compatibility (#176)

Introduce Debian 11 compatibility
Based on CIS_Debian_Linux_11_Benchmark_v1.0.0

After review, here are the notable changes :
 - Harden /var/log more (noexec,nodev,nosuid)
 - Harden /var/log/audit more (noexec,nodev,nosuid)
 - Harden /home more (nosuid)
 - Disable cramfs
 - Fix 5.3.4_acc_pam_sha512.sh
 - Deprecate Debian 9 and remove useless docker images

NB : more audit log rules have been introduced and will be inserted in the checks later
Fix #158

.github/workflows/functionnal-tests.yml

@@ -4,13 +4,6 @@ on:
   - pull_request
   - push
 jobs:
-  functionnal-tests-docker-debian9:
-    runs-on: ubuntu-latest
-    steps:
-      - name: Checkout repo
-        uses: actions/checkout@v3
-      - name: Run the tests debian9
-        run: ./tests/docker_build_and_run_tests.sh debian9
   functionnal-tests-docker-debian10:
     runs-on: ubuntu-latest
     steps: