Add StijnvWijn as a contributor for code (#1312)

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

Author: allcontributors[bot]

.all-contributorsrc

@@ -864,6 +864,15 @@
       "contributions": [
         "code"
       ]
+    },
+    {
+      "login": "StijnvWijn",
+      "name": "StijnvWijn",
+      "avatar_url": "https://avatars.githubusercontent.com/u/78531113?v=4",
+      "profile": "https://github.com/StijnvWijn",
+      "contributions": [
+        "code"
+      ]
     }
   ],
   "contributorsPerLine": 7,

README.md

@@ -409,6 +409,7 @@ Thanks goes to all these people ([emoji key](https://allcontributors.org/docs/en
     </tr>
     <tr>
       <td align="center" valign="top" width="14.28%"><a href="https://github.com/mrdkucher"><img src="https://avatars.githubusercontent.com/u/13631603?v=4?s=100" width="100px;" alt="David Kucher"/><br /><sub><b>David Kucher</b></sub></a><br /><a href="https://github.com/TorchIO-project/torchio/commits?author=mrdkucher" title="Code">💻</a></td>
+      <td align="center" valign="top" width="14.28%"><a href="https://github.com/StijnvWijn"><img src="https://avatars.githubusercontent.com/u/78531113?v=4?s=100" width="100px;" alt="StijnvWijn"/><br /><sub><b>StijnvWijn</b></sub></a><br /><a href="https://github.com/TorchIO-project/torchio/commits?author=StijnvWijn" title="Code">💻</a></td>
     </tr>
   </tbody>
 </table>