gh pr create breaks with "could not prompt" error #7651

Describe the bug

The latest update 2.31.0 installed using brew on macOS breaks with an "could not prompt" error when running gh pr create with the milestone selected via the Add metadata menu.

Maybe it's a similar issue to #7634.

Steps to reproduce the behavior

1. Set your default shell as zsh.
2. Clone a repo (probably https://github.com/lablup/backend.ai)
3. gh pr create with milestone using "Add metadata" option.

Expected vs actual behavior

It should ask for which milestone to set for the new PR.

Additional Info

With the update 2.31.0, I'm experiencing a similar issue with zsh.

After chagning the selections for "Add metadata" several times, it seems to break with the "Milestone".

If I do not include "Milestone", it seems to work fine:

You may check out the milestone configuration of the repo shown in the log here: https://github.com/lablup/backend.ai/milestones.