Automatic --signoff via settings

[bnb]

It seems that presently, you can use the -s or --signoff command on your git commits by opening up the git commit dropdown and selecting signoff. This was implemented as a "fix" for #7010 in #10410.

However, there doesn't seem to be a setting within VS Code itself that enables end-users to enable this feature as a part of their git commit messages by default without taking those extra steps of opening a dropdown and selecting the right option.

Given the prevalence of the Developer Certificate of Origin and it's hard requirement of the -s flag in massive open source projects projects like Node.js, Helm, Prometheus, and Moby, it would be super awesome to have the ability to turn this on as a setting in VS Code.

[joaomoreno]

The setting is git.alwaysSignOff