[3.12] GH-87041: Fix incorrect indentation in argparse help (GH-124230) (GH-124374)

In case of usage a long command along with max_help_position more than
the length of the command, the command's help was incorrectly started
on the new line.

(cherry picked from commit 7ee99217345af3010bf05b1f5241c661a5e0ea9b)

Co-authored-by: Savannah Ostrowski <savannahostrowski@gmail.com>
Co-authored-by: Pavel Ditenbir <pavel.ditenbir@gmail.com>