bug#55289: 29.0.50; minibuffer-next-completion errors on wrap when completion-show-help and completions-header-format are set to nil

[Juri Linkov]

> 1. Run emacs -Q
> 2. Evaluate the following form:
>    (setq completions-format 'one-column
>          completion-auto-select nil
>          completion-show-help nil
>          completions-header-format nil
>          completion-auto-help 'visual
>          completion-wrap-movement t)
> 3. Type 'M-x gnus M-<up> M-<down>'
> 4. Emacs reports error: "Wrong type argument: integer-or-marker-p, nil"

Thanks for the bug report.  It seems it's related to the last problem of
bug#54374.  So fixing bug#54374 could fix this as well.