docs: add rvdkooy as a contributor (#477)

* docs: update README.md

* docs: update .all-contributorsrc


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

Author: allcontributors[bot]

.all-contributorsrc

@@ -946,7 +946,8 @@
       "avatar_url": "https://avatars1.githubusercontent.com/u/4119960?v=4",
       "profile": "https://github.com/rvdkooy",
       "contributions": [
-        "test"
+        "test",
+        "code"
       ]
     },
     {

README.md

@@ -509,7 +509,7 @@ Thanks goes to these people ([emoji key][emojis]):
     <td align="center"><a href="https://cimbul.com"><img src="https://avatars2.githubusercontent.com/u/927923?v=4" width="100px;" alt="Tim Yates"/><br /><sub><b>Tim Yates</b></sub></a><br /><a href="#review-cimbul" title="Reviewed Pull Requests">👀</a></td>
     <td align="center"><a href="https://github.com/eventualbuddha"><img src="https://avatars3.githubusercontent.com/u/1938?v=4" width="100px;" alt="Brian Donovan"/><br /><sub><b>Brian Donovan</b></sub></a><br /><a href="https://github.com/testing-library/react-testing-library/commits?author=eventualbuddha" title="Code">💻</a></td>
     <td align="center"><a href="https://github.com/JaysQubeXon"><img src="https://avatars1.githubusercontent.com/u/18309230?v=4" width="100px;" alt="Noam Gabriel Jacobson"/><br /><sub><b>Noam Gabriel Jacobson</b></sub></a><br /><a href="https://github.com/testing-library/react-testing-library/commits?author=JaysQubeXon" title="Documentation">📖</a></td>
-    <td align="center"><a href="https://github.com/rvdkooy"><img src="https://avatars1.githubusercontent.com/u/4119960?v=4" width="100px;" alt="Ronald van der Kooij"/><br /><sub><b>Ronald van der Kooij</b></sub></a><br /><a href="https://github.com/testing-library/react-testing-library/commits?author=rvdkooy" title="Tests">⚠️</a></td>
+    <td align="center"><a href="https://github.com/rvdkooy"><img src="https://avatars1.githubusercontent.com/u/4119960?v=4" width="100px;" alt="Ronald van der Kooij"/><br /><sub><b>Ronald van der Kooij</b></sub></a><br /><a href="https://github.com/testing-library/react-testing-library/commits?author=rvdkooy" title="Tests">⚠️</a> <a href="https://github.com/testing-library/react-testing-library/commits?author=rvdkooy" title="Code">💻</a></td>
   </tr>
   <tr>
     <td align="center"><a href="https://github.com/aayushrajvanshi"><img src="https://avatars0.githubusercontent.com/u/14968551?v=4" width="100px;" alt="Aayush Rajvanshi"/><br /><sub><b>Aayush Rajvanshi</b></sub></a><br /><a href="https://github.com/testing-library/react-testing-library/commits?author=aayushrajvanshi" title="Documentation">📖</a></td>