git-signed check doesn't work as expected

git-signed check doesn't work as expected, because last commit is not checked (and if only one commit is there to please git.max-commit, then none are checked).

https://gitlab.com/Orange-OpenSource/lfn/ci_cd/gitlab-ci-templates/-/blob/master/git.signed.gitlab-ci.yml#L15

git log --pretty=format:'%h:%s' "${COMMON_ANCESTOR}..HEAD" | while read -r commit`

https://gitlab.com/Orange-OpenSource/lfn/ci_cd/gitlab-ci-templates/-/blob/master/git.signed.tbc.gitlab-ci.yml#L15

git log --pretty=format:'%h:%s' "${COMMON_ANCESTOR}..HEAD" | while read -r commit

Both should be with --pretty=tformat:'%h:%s' or --format='%h:%s'

Cf https://git-scm.com/docs/git-log#_pretty_formats (look for "NO NEWLINE")

$ printf "A" | while read -r commit ; do echo $commit ; done
$
$ printf "A\nB" | while read -r commit ; do echo $commit ; done
A
$ printf "A\nB\n" | while read -r commit ; do echo $commit ; done
A
B