Show subcommand about on same line, even in --help

[Centri3]

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• I have searched the open and rejected issues

Clap Version

master

Describe your use case

It's easier to read, of course when long_about (not just the summary) is used, putting it on the same line is less than desirable, but this always shows the summary anyway.

Example:

Usage: a <X> <COMMAND>

Commands:
  lol   This, however - since it's only showing the summary, it may be easier to digest if it's on the same line, or just cleaner (ok, that isn't a summary...)
  help  Print this message or the help of the given subcommand(s)

Arguments:
  <X>
          Really short summary
          
          Very long and descriptive, perhaps overly descriptive explanation of what
          this code does and utterly every little detail of it...
          
          Since this is NOT just the summary, it's ok to put this on multiple lines.

Options:
  -h, --help
          Print help (see a summary with '-h')

Describe the solution you'd like

Currently, line 898 in help_template.rs (or, somewhere in write_subcommands):

self.write_subcommand(sc_str, sc, next_line_help, longest);

Switch this to:

self.write_subcommand(sc_str, sc, false, longest);

This will cause clap to always show subcommands on the same line.

Alas, This is not future proof.

Alternatives, if applicable

#1334, or just no changes. It's fine currently.

Additional Context

Since it only ever shows about and not long_about for subcommands in particular, it makes sense for it to (by default) show it on the same line, since it's the summary. -h does this, and so does --help too - unless long_about is provided on anything.

if next_line_help(true) is passed, then it should preserve the current behavior of course.

[epage]

Created #4902