Action taints the workspace by adding untracked files

### TL;DR

Running secure-setup-terraform taints the workspace by adding several untracked files like `lint-action`, `lint-terraform`. It also overrides `LICENSE` and `README.md`. These changes interferes with workflows that needs these files.

### Expected behavior

All dependencies are kept in another directory separated from "$GITHUB_WORKSPACE".

### Observed behavior

_No response_

### Environment Details

```markdown
github actions
```

### Additional information

_No response_

Look at the action's entry point (likely main.go or action.yml) to see where it writes files like 'lint-action' and 'lint-terraform'. Understand the workspace layout and how to isolate dependencies. Check existing tests for file system interactions. The fix involves changing the output directory to a temporary location outside GITHUB_WORKSPACE.

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