bug#9237: [PATCH] tests: get rid of obsolete 'error_' shell function

[Jim Meyering]

Stefano Lattarini wrote:
...
>> Also, I have queued this additional change set:
...
>> Subject: [PATCH 2/2] maint: prevent accidental future use of the old shell
>>  function name

This was addressed months ago.
Closing the bug.