common/hooks: Prefill update info in commit msg

[joebonrichie]

Summary

• If the version has been changed in the package.yml as part of the commit then prefill that information in the commit header. e.g. nano: Update to 1.2.3

Test Plan

Update some pkgs, verify commit info gets prefilled.

Checklist

• Package was built and tested against unstable

[ermo]

Given that this imports new libraries, doesn't it need to be accompanied by an update to the packaging documentation for ensuring that the user installs pyyaml?

(from what I can tell, subprocess is part of the normal py3 distribution, so doesn't need to be explicitly installed)

[joebonrichie]

Normally i would agree but pyyaml needs to be installed as part of ypkg e.g. go-task bump anyway. I do wonder where the best way to check this would be?

[silkeh]

LGTM, thanks!