Push removes signatures from commits

I am running a script like the following:

echo $SIGNING_KEY | jq -r . > ~/.ssh/sign.pem
chmod 0600 ~/.ssh/sign.pem
git config gpg.format ssh
git config user.signingkey ~/.ssh/sign.pem
git config user.email ${USER_EMAIL}
git config user.name "Chat GPT Codex (on behalf of ${USER_NAME})"
git config commit.gpgsign true

with a secret called SIGNING_KEY that contains an ssh signing key in pem format encoded as a JSON string (to preserve newlines).

My goal is to sign the commits, becuase my repos require commit signing.

This script works great, except that when I push a PR in the codex ui it appears to be removing the signature and overwriting the author information.

I’m guessing this is on purpose.

Is there anyway to get codex to preserve the signature on my commits?