docs: add kandros as a contributor (#140)

* docs: update README.md

* docs: update .all-contributorsrc

Author: allcontributors[bot]

.all-contributorsrc

@@ -294,7 +294,8 @@
       "profile": "http://jagascript.com",
       "contributions": [
         "bug",
-        "test"
+        "test",
+        "doc"
       ]
     }
   ],

README.md

@@ -1074,7 +1074,7 @@ Thanks goes to these people ([emoji key][emojis]):
     <td align="center"><a href="https://github.com/YardenShoham"><img src="https://avatars3.githubusercontent.com/u/20454870?v=4" width="100px;" alt="Yarden Shoham"/><br /><sub><b>Yarden Shoham</b></sub></a><br /><a href="https://github.com/testing-library/jest-dom/commits?author=YardenShoham" title="Documentation">📖</a></td>
   </tr>
   <tr>
-    <td align="center"><a href="http://jagascript.com"><img src="https://avatars0.githubusercontent.com/u/4562878?v=4" width="100px;" alt="Jaga Santagostino"/><br /><sub><b>Jaga Santagostino</b></sub></a><br /><a href="https://github.com/testing-library/jest-dom/issues?q=author%3Akandros" title="Bug reports">🐛</a> <a href="https://github.com/testing-library/jest-dom/commits?author=kandros" title="Tests">⚠️</a></td>
+    <td align="center"><a href="http://jagascript.com"><img src="https://avatars0.githubusercontent.com/u/4562878?v=4" width="100px;" alt="Jaga Santagostino"/><br /><sub><b>Jaga Santagostino</b></sub></a><br /><a href="https://github.com/testing-library/jest-dom/issues?q=author%3Akandros" title="Bug reports">🐛</a> <a href="https://github.com/testing-library/jest-dom/commits?author=kandros" title="Tests">⚠️</a> <a href="https://github.com/testing-library/jest-dom/commits?author=kandros" title="Documentation">📖</a></td>
   </tr>
 </table>