chore(deps): update zricethezav/gitleaks docker tag to v8.18.1 (#686)

This PR contains the following updates:

| Package | Update | Change |
|---|---|---|
| [zricethezav/gitleaks](https://github.com/gitleaks/gitleaks) | patch | `v8.18.0` -> `v8.18.1` |

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Reviewed-on: #686
Co-authored-by: Renovate Bot <renovate@mgrote.net>
Co-committed-by: Renovate Bot <renovate@mgrote.net>

.woodpecker/gitleaks.yml

@@ -1,7 +1,7 @@
 ---
 steps:
   gitleaks:
-    image: zricethezav/gitleaks:v8.18.0@sha256:6945c62ca019ead32bc337ab0c9fd055e98d82961765d38b7ccccc84dae95d0f
+    image: zricethezav/gitleaks:v8.18.1@sha256:6945c62ca019ead32bc337ab0c9fd055e98d82961765d38b7ccccc84dae95d0f
     commands:
       - gitleaks detect --no-git --verbose --source $CI_WORKSPACE
     when: