fix(credentials): update Facebook Graph API to v24.0

[sdass1918]

Summary

This PR updates the hardcoded version of the Facebook Graph API used for credential testing from the deprecated v8.0 to the current v24.0.

The previous version (v8.0) has been discontinued by Meta, causing the credential validation request to fail. This prevented users from successfully connecting new Facebook Graph API credentials, even with a valid access token. Updating the API version in the test request to a supported version resolves this issue.

To Test:

1. Create a new node and search for "Facebook Graph API".
2. Click the credential to connect with and create new credential.
3. Fill in the personal access token and click save button.
4. The connection should be tested successfully.

Result:

Related Linear tickets, Github issues, and Community forum posts

Closes #20683

Review / Merge checklist

• PR title and summary are descriptive. (conventions)
• Docs updated or follow-up ticket created.
• Tests included.
• PR Labeled with release/backport (if the PR is an urgent fix that needs to be backported)

[CLAassistant]

Thank you for your submission! We really appreciate it. Like many open source projects, we ask that you sign our Contributor License Agreement before we can accept your contribution.
_{You have signed the CLA already but the status is still pending? Let us recheck it.}

[cubic-dev-ai]

No issues found across 1 file

[n8n-assistant]

Hey @sdass1918,

Thank you for your contribution. We appreciate the time and effort you’ve taken to submit this pull request.

Before we can proceed, please ensure the following:
• Tests are included for any new functionality, logic changes or bug fixes.
• The PR aligns with our contribution guidelines.

Regarding new nodes:
We no longer accept new nodes directly into the core codebase. Instead, we encourage contributors to follow our Community Node Submission Guide to publish nodes independently.

If your node integrates with an AI service that you own or represent, please email [email protected] and we will be happy to discuss the best approach.

About review timelines:
This PR has been added to our internal tracker as "GHC-4990". While we plan to review it, we are currently unable to provide an exact timeframe. Our goal is to begin reviews within a month, but this may change depending on team priorities. We will reach out when the review begins.

Thank you again for contributing to n8n.