Update @kaishuu0123 as a contributor

Author: rtfpessoa

.all-contributorsrc

@@ -79,7 +79,8 @@
       "avatar_url": "https://avatars0.githubusercontent.com/u/1567423?v=4",
       "profile": "https://saino.me/",
       "contributions": [
-        "bug"
+        "bug",
+        "code"
       ]
     },
     {

README.md

@@ -503,7 +503,7 @@ Thanks goes to these wonderful people ([emoji key](https://allcontributors.org/d
     <td align="center"><a href="https://github.com/nmatpt"><img src="https://avatars2.githubusercontent.com/u/5034733?v=4?s=100" width="100px;" alt=""/><br /><sub><b>Nuno Teixeira</b></sub></a><br /><a href="https://github.com/rtfpessoa/diff2html/commits?author=nmatpt" title="Code">💻</a></td>
   </tr>
   <tr>
-    <td align="center"><a href="https://saino.me/"><img src="https://avatars0.githubusercontent.com/u/1567423?v=4?s=100" width="100px;" alt=""/><br /><sub><b>Koki Oyatsu</b></sub></a><br /><a href="https://github.com/rtfpessoa/diff2html/issues?q=author%3Akaishuu0123" title="Bug reports">🐛</a></td>
+    <td align="center"><a href="https://saino.me/"><img src="https://avatars0.githubusercontent.com/u/1567423?v=4?s=100" width="100px;" alt=""/><br /><sub><b>Koki Oyatsu</b></sub></a><br /><a href="https://github.com/rtfpessoa/diff2html/issues?q=author%3Akaishuu0123" title="Bug reports">🐛</a> <a href="https://github.com/rtfpessoa/diff2html/commits?author=kaishuu0123" title="Code">💻</a></td>
     <td align="center"><a href="http://www.jamesmonger.com"><img src="https://avatars2.githubusercontent.com/u/2037007?v=4?s=100" width="100px;" alt=""/><br /><sub><b>James Monger</b></sub></a><br /><a href="https://github.com/rtfpessoa/diff2html/commits?author=Jameskmonger" title="Documentation">📖</a></td>
     <td align="center"><a href="http://wesssel.github.io/"><img src="https://avatars2.githubusercontent.com/u/7767299?v=4?s=100" width="100px;" alt=""/><br /><sub><b>Wessel van der Pal</b></sub></a><br /><a href="#security-wesssel" title="Security">🛡️</a></td>
     <td align="center"><a href="https://jung-kim.github.io"><img src="https://avatars2.githubusercontent.com/u/5281068?v=4?s=100" width="100px;" alt=""/><br /><sub><b>jk-kim</b></sub></a><br /><a href="https://github.com/rtfpessoa/diff2html/commits?author=jung-kim" title="Code">💻</a></td>