Resolving Pull Request conflicts from web editor

[antonlnz]

Feature Description

I think it would be a very nice feature to be able to resolve pull request conflicts GitHub style. If I'm not wrong this is not supported right now. This website shows what I am referring to in the "Resolve within GitHub's Web Editor" section. I attach photos anyway

Screenshots

[delvh]

Duplicate of at least #9014, and probably others.