new Github action for diff-cover

[itayB]

Hi there!

As we heavily use diff_cover, we are also a big fun of this repo!
It helped us to improve our programming skills, find bugs faster, increase our coverage and our motivation to write tests :)

My colleague Asaf recently release a new Tests Coverage Report Github actions based on this great repo.
He would like to get feedback and help more users to use this great diff coverage capability!

Thanks

[zhaolijunstar]

You have used diff-cover a lot, would like to ask if you have encountered the same problem as #346, please help