add server-side hook: proc-receive

[Cactusinhand]

• I provide my work under the project license.
• I grant such license of my work as is required for the purposes of future print editions to Ben Straub and Scott Chacon.

Changes

• Add new server side hook proc-receive

Context

In git hooks, a new server side hook named proc-receive have been added in 2020. This is a very usefully hook, I think it shoud be known by more people, especialy the readers of this book.

[Cactusinhand]

Hi, @jiangxin I may need your input on this change, please correct me if I'm missing anything.