List one hash in "Some good revs are not ancestors of the bad rev."

[Paul Menzel <pmenzel@xxxxxxxxxxxxx>]

Dear git folks,


With

    $ git version
    git version 2.26.2

during `git bisect` I got:

> Some good revs are not ancestors of the bad rev.
> git bisect cannot work properly in this case.
> Maybe you mistook good and bad revs?

It would be great, if the (“closest”) conflicting rev could be printed 
too, so the user can easily check it.


Kind regards,

Paul