feat(integrations): add API rate limiting to Front (#3101)

<!-- Describe the problem and your solution --> 
Add rate limiting to both the documentation and the `providers.yaml`. 
<!-- Issue ticket number and link (if applicable) -->

<!-- Testing instructions (skip if just adding/editing providers) -->

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Co-authored-by: Hassan Wari <[email protected]>

docs-v2/integrations/all/front.mdx

@@ -21,6 +21,7 @@ API configuration: [`front`](https://nango.dev/providers.yaml)
 
 -   [How to register an Application](https://dev.frontapp.com/docs/create-and-manage-apps#obtain-oauth-credentials-for-your-app)
 -   [OAuth-related docs](https://dev.frontapp.com/docs/oauth)
+-   [API rate limiting](https://dev.frontapp.com/docs/rate-limiting)
 -   [API](https://dev.frontapp.com/reference/introduction)
 
 <Tip>Need help getting started? Get help in the [community](https://nango.dev/slack).</Tip>

packages/shared/providers.yaml

@@ -2554,6 +2554,8 @@ front:
     token_url: https://app.frontapp.com/oauth/token
     proxy:
         base_url: https://api2.frontapp.com
+        retry:
+            after: 'Retry-after'
         paginate:
             type: link
             response_path: _results