Improve MeshDataTool.get_face_vertex() method description

[mateuseap]

What I did

• Improved the MeshDataTool.get_face_vertex() method description by making it more clear about what is the data type that is returned and adding a code example.

Closes: #7852 (issue from godot-docs repo)

[AThousandShips]

Would need a c# example as well, @raulsntos?

[clayjohn]

Looks great! The final step before merging is to squash all the commits together so that the whole PR only contains 1 big commit with all your changes. We like to merge one commit at a time to keep the git history clean and navigable.

If you don't know how to do that, we have a helpful tutorial in the official documentation https://docs.godotengine.org/en/latest/community/contributing/pr_workflow.html#the-interactive-rebase

[akien-mga]

I would also suggest rewording the commit message as we don't use this format usually. The title of this PR is a good match for our usual commit style (you can see other examples in git log).

[mateuseap]

I would also suggest rewording the commit message as we don't use this format usually. The title of this PR is a good match for our usual commit style (you can see other examples in git log).

@akien-mga thanks for this suggestion!

[clayjohn]

The content looks great! Thank you

[mateuseap]

@clayjohn the commit description wasn't looking good so I just adjusted it, sorry for the delay!

[akien-mga]

Thanks!

[YuriSizov]

Cherry-picked for 4.1.3.