env_setup.md: Include setting up GPG keys and signed commits
Problem to solve
I had to rely on third-party documentation on how to set up GPG signing for commits, and I'd like to change that.
Not entirely sure if this is in scope, though. Let me know, I'll prepare a MR.
Proposal
An optional step-by-step guide on the "Configure your environment" page on how to
- Generate a GPG keypair for the
user.email
- Select said GPG key as
user.signingkey
. - Set
commit.gpgsign
totrue
- Maybe include the pinentry workaround for Mac, if that's a widespread issue?