push_rule_committer_not_verified string contains a typo in the variable interpolation

f5d2d237 introduced a typo in the push_rule_committer_not_verified String, so when the shell returns this error it's not interpolated correctly:

Counting objects: 4, done.
Delta compression using up to 8 threads.
Compressing objects: 100% (4/4), done.
Writing objects: 100% (4/4), 2.03 KiB | 2.03 MiB/s, done.
Total 4 (delta 1), reused 0 (delta 0)
remote: GitLab: Comitter email '%{commiter_email}' is not verified.
To gitlab.com:gitlab-com/chatops.git
 ! [remote rejected] rs-fake-slack-payload -> rs-fake-slack-payload (pre-receive hook declined)
error: failed to push some refs to 'git@gitlab.com:gitlab-com/chatops.git'