docs: add 9still as a contributor (#284)

* docs: update README.md

* docs: update .all-contributorsrc

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

.all-contributorsrc

@@ -292,6 +292,17 @@
         "code",
         "test"
       ]
+    },
+    {
+      "login": "9still",
+      "name": "Greg Shtilman",
+      "avatar_url": "https://avatars0.githubusercontent.com/u/4924760?v=4",
+      "profile": "https://github.com/9still",
+      "contributions": [
+        "code",
+        "test",
+        "bug"
+      ]
     }
   ],
   "commitConvention": "none",

README.md

@@ -337,6 +337,7 @@ Thanks goes to these wonderful people
   </tr>
   <tr>
     <td align="center"><a href="https://proling.ru/"><img src="https://avatars2.githubusercontent.com/u/16336572?v=4" width="100px;" alt=""/><br /><sub><b>Vadim Shvetsov</b></sub></a><br /><a href="#ideas-vadimshvetsov" title="Ideas, Planning, & Feedback">🤔</a> <a href="https://github.com/testing-library/user-event/commits?author=vadimshvetsov" title="Code">💻</a> <a href="https://github.com/testing-library/user-event/commits?author=vadimshvetsov" title="Tests">⚠️</a></td>
+    <td align="center"><a href="https://github.com/9still"><img src="https://avatars0.githubusercontent.com/u/4924760?v=4" width="100px;" alt=""/><br /><sub><b>Greg Shtilman</b></sub></a><br /><a href="https://github.com/testing-library/user-event/commits?author=9still" title="Code">💻</a> <a href="https://github.com/testing-library/user-event/commits?author=9still" title="Tests">⚠️</a> <a href="https://github.com/testing-library/user-event/issues?q=author%3A9still" title="Bug reports">🐛</a></td>
   </tr>
 </table>