docs: add pull-request section (#233)

* docs: add pull-request page

* Update pullRequest.md

Author: eunjae-lee

website/docs/pullRequest.md

@@ -0,0 +1,7 @@
+---
+title: Pull-request
+---
+
+# Pull-request
+
+Semantic title is required. It's validated by [GitHub Action](https://github.com/deepakputhraya/action-pr-title). See [pr-title.yml](https://github.com/algolia/api-clients-automation/blob/main/.github/workflows/pr-title.yml) for the complete regular expressions.

website/sidebars.js

@@ -19,6 +19,7 @@ const sidebars = {
         },
         'addNewClient',
         'addNewLanguage',
+        'pullRequest',
       ],
     },
     {