[Feature] Support for .net monorepos

[rocklan]

Is this feature missing in the latest version?

• [x] I'm using the latest release

Is your feature request related to a problem? Please describe.

It would be great if this action could support .NET .slnf files. This would be massively helpful for .NET monorepo's.

Describe the solution you'd like?

Possible solution here: https://github.com/tj-actions/changed-files/pull/2579

Describe alternatives you've considered?

It's possible to generate the JSON file outside of this action but it would be quicker and easier to use if it was built-in instead.

Anything else?

No response

Code of Conduct

• [x] I agree to follow this project's Code of Conduct