In _send_signed_request and _check_dns_entries, return 1 when the
timeout (or number of retries) has been exhausted. This allows
the calling function to correctly handle the error.
In _debug_bash_helper use eval as we are seeing issues with busybox
systems having issues with array access. Even though they aren't
actually running the code they appear to be parsing it and failing.
Also older versions of busybox have a bug with eval and double quotes,
so make sure to use single quotes when using eval.
Resolves: #2579