docs: add mietzen as a contributor for bug (#1883)

* docs: update CONTRIBUTORS.md

* docs: update .all-contributorsrc

---------

Co-authored-by: allcontributors[bot] <46447321+allcontributors[bot]@users.noreply.github.com>

.all-contributorsrc

@@ -1941,6 +1941,15 @@
       "contributions": [
         "bug"
       ]
+    },
+    {
+      "login": "mietzen",
+      "name": "Nils",
+      "avatar_url": "https://avatars.githubusercontent.com/u/31704359?v=4",
+      "profile": "https://github.com/mietzen",
+      "contributions": [
+        "bug"
+      ]
     }
   ],
   "repoType": "github",

CONTRIBUTORS.md

@@ -283,6 +283,7 @@ Thanks goes to these wonderful people ([emoji key](https://github.com/kentcdodds
     <tr>
       <td align="center" valign="top" width="14.28%"><a href="https://github.com/subframe7536"><img src="https://avatars.githubusercontent.com/u/78338239?v=4?s=100" width="100px;" alt="Song"/><br /><sub><b>Song</b></sub></a><br /><a href="https://github.com/ryanoasis/nerd-fonts/issues?q=author%3Asubframe7536" title="Bug reports">🐛</a></td>
       <td align="center" valign="top" width="14.28%"><a href="https://github.com/oktoling"><img src="https://avatars.githubusercontent.com/u/161823820?v=4?s=100" width="100px;" alt="an octoling"/><br /><sub><b>an octoling</b></sub></a><br /><a href="https://github.com/ryanoasis/nerd-fonts/issues?q=author%3Aoktoling" title="Bug reports">🐛</a></td>
+      <td align="center" valign="top" width="14.28%"><a href="https://github.com/mietzen"><img src="https://avatars.githubusercontent.com/u/31704359?v=4?s=100" width="100px;" alt="Nils"/><br /><sub><b>Nils</b></sub></a><br /><a href="https://github.com/ryanoasis/nerd-fonts/issues?q=author%3Amietzen" title="Bug reports">🐛</a></td>
     </tr>
   </tbody>
 </table>