Correct fetch_depth to fetch-depth

Author: patrick-5546

.github/workflows/pythonpublish.yml

@@ -10,7 +10,7 @@ jobs:
     steps:
     - uses: actions/checkout@v2
       with:
-        fetch_depth: '0'
+        fetch-depth: '0'
     - name: Set up Python
       uses: actions/setup-python@v2
       with:

README.md

@@ -46,7 +46,7 @@ This plugin needs access to the last commit that touched a specific file to be a
 <details>
   <summary>Change your CI settings</summary>
     <ul>
-      <li>github actions: set <code>fetch_depth</code> to <code>0</code> (<a href="https://github.com/actions/checkout">docs</a>)</li>
+      <li>github actions: set <code>fetch-depth</code> to <code>0</code> (<a href="https://github.com/actions/checkout">docs</a>)</li>
       <li>gitlab runners: set <code>GIT_DEPTH</code> to <code>0</code> (<a href="https://docs.gitlab.com/ee/user/project/pipelines/settings.html#git-shallow-clone">docs</a>)</li>
       <li>bitbucket pipelines: set <code>clone: depth: full</code> (<a href="https://support.atlassian.com/bitbucket-cloud/docs/configure-bitbucket-pipelinesyml/">docs</a>)</li>
     </ul>