Ambiguous verification response when ssh-based signatures

Thank you for filling out a Git bug report! Please answer the following questions to help us understand your issue.

What did you do before the bug happened? (Steps to reproduce your issue)

$ ssh-keygen -t ed25519 -C "me@example.com"
$ mkdir -pv ~/tmp/example && cd ~/tmp/example && git init
$ git config commit.gpgsign true
$ git config gpg.format ssh
$ git config user.signingkey "$(cat ~/.ssh/id_ed25519.pub)"
$ mkdir -p ~/.config/git/ && touch ~/.config/git/allowed_signers\
 && chmod 0600 ~/.config/git/allowed_signers
$ cat ~/.ssh/id_ed25519.pub | awk '{print email " " $0}' email=$(git
config user.email)\
 >> ~/.config/git/allowed_signers
$ git config gpg.ssh.allowedSignersFile "$HOME/.config/git/allowed_signers"
$ git commit --allow-empty -m "Initial commit"
$ git verify-commit HEAD

What did you expect to happen? (Expected behavior)

A verified signature without any error message.

What happened instead? (Actual behavior)

$ git verify-commit HEAD Good "git" signature with ED25519 key SHA256:... Too few arguments for sign/verify: missing namespace $ git log --show-signature commit 4697b474dd5ec0de14870d5b0eba5f579b852bbd (HEAD -> main) Good "git" signature with ED25519 key SHA256:... Too few arguments for sign/verify: missing namespace^M

What's different between what you expected and what actually happened?

Ambiguous signature verification message.

Anything else you want to add:

Please review the rest of the bug report below. You can delete any lines you don't wish to share.

[System Info] git version: git version 2.34.0 cpu: x86_64 no commit associated with this build sizeof-long: 8 sizeof-size_t: 8 shell-path: /bin/sh uname: Darwin 20.6.0 Darwin Kernel Version 20.6.0: Mon Aug 30 06:12:21 PDT 2021; root:xnu-7195.141.6~3/RELEASE_X86_64 x86_64 compiler info: clang: 13.0.0 (clang-1300.0.29.3) libc info: no libc information available $SHELL (typically, interactive shell): /usr/local/bin/bash

[Enabled Hooks]