Add --retry_on_timeout to testservers_check_cmd_*
To match https://gerrit.wikimedia.org/r/c/operations/puppet/+/1015071
Bug: T360867
How to register an account on GitLab. To prevent spam, new accounts are locked until approved by an admin or the approver bot. You can also file an unlock request to expedite access.
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To match https://gerrit.wikimedia.org/r/c/operations/puppet/+/1015071
Bug: T360867