docs: add antonhalim as a contributor (testing-library#775)

* docs: update README.md

* docs: update .all-contributorsrc

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

Author: allcontributors[bot]

.all-contributorsrc

@@ -1149,6 +1149,15 @@
       "contributions": [
         "maintenance"
       ]
+    },
+    {
+      "login": "antonhalim",
+      "name": "Anton Halim",
+      "avatar_url": "https://avatars1.githubusercontent.com/u/10498035?v=4",
+      "profile": "https://antonhalim.com",
+      "contributions": [
+        "doc"
+      ]
     }
   ],
   "contributorsPerLine": 7,

README.md

@@ -592,6 +592,9 @@ Thanks goes to these people ([emoji key][emojis]):
     <td align="center"><a href="https://twitter.com/matanbobi"><img src="https://avatars2.githubusercontent.com/u/12711091?v=4" width="100px;" alt=""/><br /><sub><b>Matan Borenkraout</b></sub></a><br /><a href="https://github.com/testing-library/react-testing-library/commits?author=MatanBobi" title="Code">💻</a></td>
     <td align="center"><a href="http://ryanbigg.com"><img src="https://avatars3.githubusercontent.com/u/2687?v=4" width="100px;" alt=""/><br /><sub><b>Ryan Bigg</b></sub></a><br /><a href="#maintenance-radar" title="Maintenance">🚧</a></td>
   </tr>
+  <tr>
+    <td align="center"><a href="https://antonhalim.com"><img src="https://avatars1.githubusercontent.com/u/10498035?v=4" width="100px;" alt=""/><br /><sub><b>Anton Halim</b></sub></a><br /><a href="https://github.com/testing-library/react-testing-library/commits?author=antonhalim" title="Documentation">📖</a></td>
+  </tr>
 </table>
 
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