docs: add pustovalov as a contributor (#505)

* 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

@@ -831,6 +831,15 @@
       "contributions": [
         "code"
       ]
+    },
+    {
+      "login": "pustovalov",
+      "name": "Pavel Pustovalov",
+      "avatar_url": "https://avatars2.githubusercontent.com/u/1568885?v=4",
+      "profile": "http://pustovalov.dev",
+      "contributions": [
+        "doc"
+      ]
     }
   ],
   "repoHost": "https://github.com"

README.md

@@ -239,6 +239,9 @@ Thanks goes to these people ([emoji key][emojis]):
     <td align="center"><a href="https://twitter.com/minh_ngvyen"><img src="https://avatars3.githubusercontent.com/u/2852660?v=4" width="100px;" alt=""/><br /><sub><b>Minh Nguyen</b></sub></a><br /><a href="https://github.com/testing-library/dom-testing-library/commits?author=NMinhNguyen" title="Code">💻</a></td>
     <td align="center"><a href="https://github.com/egilsster"><img src="https://avatars0.githubusercontent.com/u/5672257?v=4" width="100px;" alt=""/><br /><sub><b>Egill Sveinbjörnsson</b></sub></a><br /><a href="https://github.com/testing-library/dom-testing-library/commits?author=egilsster" title="Code">💻</a></td>
   </tr>
+  <tr>
+    <td align="center"><a href="http://pustovalov.dev"><img src="https://avatars2.githubusercontent.com/u/1568885?v=4" width="100px;" alt=""/><br /><sub><b>Pavel Pustovalov</b></sub></a><br /><a href="https://github.com/testing-library/dom-testing-library/commits?author=pustovalov" title="Documentation">📖</a></td>
+  </tr>
 </table>
 
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