add SandraFer as a contributor for code (py-pdf#946)

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

.all-contributorsrc

@@ -973,7 +973,8 @@
       "avatar_url": "https://avatars.githubusercontent.com/u/50599578?v=4",
       "profile": "https://github.com/SandraFer",
       "contributions": [
-        "ideas"
+        "ideas",
+        "code"
       ]
     },
     {

README.md

@@ -251,7 +251,7 @@ This library could only exist thanks to the dedication of many volunteers around
     </tr>
     <tr>
       <td align="center" valign="top" width="14.28%"><a href="https://github.com/Niwo1403"><img src="https://avatars.githubusercontent.com/u/25332593?v=4?s=100" width="100px;" alt="Nicolai Wolfrom"/><br /><sub><b>Nicolai Wolfrom</b></sub></a><br /><a href="https://github.com/py-pdf/fpdf2/issues?q=author%3ANiwo1403" title="Bug reports">🐛</a></td>
-      <td align="center" valign="top" width="14.28%"><a href="https://github.com/SandraFer"><img src="https://avatars.githubusercontent.com/u/50599578?v=4?s=100" width="100px;" alt="Sandra"/><br /><sub><b>Sandra</b></sub></a><br /><a href="#ideas-SandraFer" title="Ideas, Planning, & Feedback">🤔</a></td>
+      <td align="center" valign="top" width="14.28%"><a href="https://github.com/SandraFer"><img src="https://avatars.githubusercontent.com/u/50599578?v=4?s=100" width="100px;" alt="Sandra"/><br /><sub><b>Sandra</b></sub></a><br /><a href="#ideas-SandraFer" title="Ideas, Planning, & Feedback">🤔</a> <a href="https://github.com/py-pdf/fpdf2/commits?author=SandraFer" title="Code">💻</a></td>
       <td align="center" valign="top" width="14.28%"><a href="https://github.com/navitho"><img src="https://avatars.githubusercontent.com/u/48886097?v=4?s=100" width="100px;" alt="navitho"/><br /><sub><b>navitho</b></sub></a><br /><a href="https://github.com/py-pdf/fpdf2/issues?q=author%3Anavitho" title="Bug reports">🐛</a></td>
     </tr>
   </tbody>