Woodpecker CI: use built-in clone, fix CoreDNS DNS resolution [CI SKIP]

- Switch from custom clone override to woodpeckerci/plugin-git built-in clone
  (handles auth automatically via netrc from GitHub OAuth token)
- Add 8.8.8.8 and 1.1.1.1 as CoreDNS upstream resolvers alongside pfSense
  (fixes intermittent DNS timeouts causing clone failures)
- Fix missing comma after heredoc in audit-policy.tf (syntax error)

stacks/platform/modules/technitium/main.tf

@@ -50,9 +50,7 @@ resource "kubernetes_config_map" "coredns" {
               ttl 30
           }
           prometheus :9153
-          #forward . 1.1.1.1
-          forward . 10.0.20.1
-          #forward . /etc/resolv.conf
+          forward . 8.8.8.8 1.1.1.1 10.0.20.1
           cache {
             success 10000 300 6
             denial 10000 300 60