Cherry-pick does not honour "Commit email" setting for author

Apparently the origin of the "commit email" feature is to allow people to hide their actual email address.

When cherry-picking, the actual address is not hidden, because "commit email" is used only for "committer", and still shown for "author".

This behaviour is surprising because it seems to not meet the explicit purpose of the feature.

$ git cat-file commit origin/cherry-pick-462a299c-2
tree 21cc5d9ab89033e4b67911446328cc94bbf25699
parent b8473f5b8eda008cf98349961af077f6763bc5ae
author Aaron Bentley <abentley@imax.com> 1743784541 +0000
committer Aaron Bentley <aaron.bentley@ssimwave.com> 1743784541 +0000

Merge branch 'feature/update-nathan-ip' into 'develop'

update Nathan's ip address for optimizer and insights clusters

New IP, so update the insights and optimizer allow lists.

See merge request https://gitlab.com/ssimwave/big/big/-/merge_requests/9360

(cherry picked from commit 462a299ce3dbf5f66b5a58b678538523cc3aa03b)

85af9eef update Nathan's ip address for optimizer and insights clusters

Co-authored-by: Nathan Wormsbecker <nathan.wormsbecker@ssimwave.com>

I had wished to use the feature differently, as part of a migration. Our SAML integration requires a specific user email domain to be set, but until the migration is complete, we want to use a different email domain and enforce it with push rules. But setting the push rule to exclude @imax.com means that cherry-picks are rejected due to the author email.

It's possibly also wrong for the "Commit author's email" regex to care about both the committer and author email. There are scenarios where work originally authored by an unapproved user is then committed by an approved user. In these scenarios, the approved user is vouching for the work of the unapproved user, and so only the committer email should matter.