docs: add michael-siek as a contributor (#706)

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

Author: allcontributors[bot]

.all-contributorsrc

@@ -1102,6 +1102,15 @@
       "contributions": [
         "doc"
       ]
+    },
+    {
+      "login": "michael-siek",
+      "name": "Michael",
+      "avatar_url": "https://avatars0.githubusercontent.com/u/45568605?v=4",
+      "profile": "http://michaelsiek.com",
+      "contributions": [
+        "doc"
+      ]
     }
   ],
   "contributorsPerLine": 7,

README.md

@@ -585,6 +585,7 @@ Thanks goes to these people ([emoji key][emojis]):
   <tr>
     <td align="center"><a href="https://github.com/NiGhTTraX"><img src="https://avatars0.githubusercontent.com/u/485061?v=4" width="100px;" alt=""/><br /><sub><b>Andrei Picus</b></sub></a><br /><a href="https://github.com/testing-library/react-testing-library/issues?q=author%3ANiGhTTraX" title="Bug reports">🐛</a> <a href="https://github.com/testing-library/react-testing-library/pulls?q=is%3Apr+reviewed-by%3ANiGhTTraX" title="Reviewed Pull Requests">👀</a></td>
     <td align="center"><a href="https://redd.one"><img src="https://avatars3.githubusercontent.com/u/14984911?v=4" width="100px;" alt=""/><br /><sub><b>Artem Zakharchenko</b></sub></a><br /><a href="https://github.com/testing-library/react-testing-library/commits?author=kettanaito" title="Documentation">📖</a></td>
+    <td align="center"><a href="http://michaelsiek.com"><img src="https://avatars0.githubusercontent.com/u/45568605?v=4" width="100px;" alt=""/><br /><sub><b>Michael</b></sub></a><br /><a href="https://github.com/testing-library/react-testing-library/commits?author=michael-siek" title="Documentation">📖</a></td>
   </tr>
 </table>