docs: add JohannesFischer as a contributor for code (#745)

* docs: update README.md

* docs: update .all-contributorsrc

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

.all-contributorsrc

@@ -939,6 +939,15 @@
       "contributions": [
         "code"
       ]
+    },
+    {
+      "login": "JohannesFischer",
+      "name": "Johannes Fischer",
+      "avatar_url": "https://avatars.githubusercontent.com/u/28100?v=4",
+      "profile": "https://johannesfischer.github.io/",
+      "contributions": [
+        "code"
+      ]
     }
   ],
   "commitConvention": "none",

README.md

@@ -254,6 +254,7 @@ Thanks goes to these people ([emoji key][emojis]):
     <td align="center"><a href="https://github.com/eventualbuddha"><img src="https://avatars.githubusercontent.com/u/1938?v=4?s=100" width="100px;" alt=""/><br /><sub><b>Brian Donovan</b></sub></a><br /><a href="https://github.com/testing-library/user-event/commits?author=eventualbuddha" title="Code">💻</a></td>
     <td align="center"><a href="http://www.largetimber.com"><img src="https://avatars.githubusercontent.com/u/10626756?v=4?s=100" width="100px;" alt=""/><br /><sub><b>Eric Wang</b></sub></a><br /><a href="https://github.com/testing-library/user-event/commits?author=fa93hws" title="Code">💻</a></td>
     <td align="center"><a href="https://github.com/jesperorb"><img src="https://avatars.githubusercontent.com/u/21122051?v=4?s=100" width="100px;" alt=""/><br /><sub><b>Jesper Orb</b></sub></a><br /><a href="https://github.com/testing-library/user-event/commits?author=jesperorb" title="Code">💻</a></td>
+    <td align="center"><a href="https://johannesfischer.github.io/"><img src="https://avatars.githubusercontent.com/u/28100?v=4?s=100" width="100px;" alt=""/><br /><sub><b>Johannes Fischer</b></sub></a><br /><a href="https://github.com/testing-library/user-event/commits?author=JohannesFischer" title="Code">💻</a></td>
   </tr>
 </table>