docs: update README.md

Author: allcontributors[bot]

README.md

@@ -291,6 +291,7 @@ Thanks goes to these people ([emoji key][emojis]):
     <td align="center"><a href="https://ashertuggle.wixsite.com/portfolio"><img src="https://avatars2.githubusercontent.com/u/10679635?v=4" width="100px;" alt=""/><br /><sub><b>Asher Tuggle</b></sub></a><br /><a href="https://github.com/testing-library/dom-testing-library/issues?q=author%3Aawesomeunleashed" title="Bug reports">🐛</a></td>
     <td align="center"><a href="https://github.com/winterlamon"><img src="https://avatars0.githubusercontent.com/u/16295605?v=4" width="100px;" alt=""/><br /><sub><b>Winter LaMon</b></sub></a><br /><a href="https://github.com/testing-library/dom-testing-library/commits?author=winterlamon" title="Code">💻</a> <a href="https://github.com/testing-library/dom-testing-library/commits?author=winterlamon" title="Tests">⚠️</a></td>
     <td align="center"><a href="http://victorandcode.com"><img src="https://avatars0.githubusercontent.com/u/18427801?v=4" width="100px;" alt=""/><br /><sub><b>Victor Cordova</b></sub></a><br /><a href="https://github.com/testing-library/dom-testing-library/commits?author=victorandcode" title="Code">💻</a> <a href="https://github.com/testing-library/dom-testing-library/commits?author=victorandcode" title="Tests">⚠️</a></td>
+    <td align="center"><a href="https://github.com/slowselfip"><img src="https://avatars3.githubusercontent.com/u/9762906?v=4" width="100px;" alt=""/><br /><sub><b>slowselfip</b></sub></a><br /><a href="https://github.com/testing-library/dom-testing-library/issues?q=author%3Aslowselfip" title="Bug reports">🐛</a></td>
   </tr>
 </table>