Update README for new input

README.md

@@ -82,6 +82,7 @@ jobs:
 | `stack-build-arguments-test`         | <p>Additional arguments passed after <code>stack-build-arguments</code> in <code>stack build</code> invocations on the <em>Test</em> step.</p>                                                                                                 | `false`  | `""`                |
 | `cache-prefix`                       | <p>Prefix applied to all cache keys. This can be any value you like, but teams often use <code>v{N}</code> and bump it to <code>v{N+1}</code> when/if they need to explicitly bust caches.</p>                                                 | `false`  | `""`                |
 | `cache-save-always`                  | <p>Save artifacts to the cache even if the build fails. This may speed up builds in subsequent runs at the expense of slightly-longer builds when a full cache-hit occurs. Since <code>@v4.2.0</code>.</p>                                     | `false`  | `false`             |
+| `on-dirty-files`                     | <p>What to do if we find changes to the cabal or lock file after a build. Value can be <code>warn</code>, or <code>error</code>. Default is <code>warn</code>.</p>                                                                             | `false`  | `warn`              |
 | `install-stack`                      | <p>Install stack, if necessary</p>                                                                                                                                                                                                             | `false`  | `true`              |
 | `upgrade-stack`                      | <p>Upgrade stack</p>                                                                                                                                                                                                                           | `false`  | `true`              |
 | `compiler-tools`                     | <p>A list of packages to install as compiler tools, one per line. This is useful to do here rather than separate <code>run</code> commands so that their installation is incorporated in the dependency cache. Since <code>@v5.2.0</code>.</p> | `false`  | `""`                |