[Bug]: Edit button does not link properly to index.md files

[dwightjl]

Describe the bug

https://docs.chain.link/data-feeds

The "Edit this page" button links to here: https://github.com/smartcontractkit/documentation/tree/main/src/pages/data-feeds.md

The actual file is here:
https://github.com/smartcontractkit/documentation/blob/main/src/pages/data-feeds/index.mdx

To Reproduce

Use the edit this page button here: https://docs.chain.link/data-feeds

URLs

[- https://docs.chain.link/..

• ...
  ](https://docs.chain.link/data-feeds)

Expected behavior

Opening the correct file on GitHub

Additional context

No response

[thedriftofwords]

https://github.com/smartcontractkit/documentation/blob/main/src/layouts/MainLayout.astro#L16-L18 <-- Where the GitHub edit URL is set. Either we add some custom logic to handle the index files or see if there's something in Astro that provides the filename as a variable.