[PATCH] asciidoctor: fix `synopsis` rendering

From: Johannes Schindelin <johannes.schindelin@gmx.de>

Since 76880f0510c (doc: git-clone: apply new documentation formatting guidelines, 2024-03-29), the synopsis of `git clone`'s manual page is rendered differently than before; Its parent commit did the same for `git init`.

The result looks quite nice. When rendered with AsciiDoc, that is. When rendered using AsciiDoctor, the result is quite unpleasant to my eye, reading something like this:

	SYNOPSIS

	 git clone
	  [
	 --template=
	 <template-directory>]
		  [
	 -l
	 ] [
	 -s
	 ] [
	 --no-hardlinks
	 ] [
	 -q
	 ] [
	[... continuing like this ...]

Even on the Git home page, where AsciiDoctor's default stylesheet is not used, this change results in some unpleasant rendering where not only the font is changed for the `<code>` sections of the synopsis, but padding and a different background color make the visual impression quite uneven: compare https://git-scm.com/docs/git-clone/2.45.0 to https://git-scm.com/docs/git-clone/2.44.0.

To fix this, let's apply the method recommended by AsciiDoctor in https://docs.asciidoctor.org/asciidoctor/latest/html-backend/default-stylesheet/#customize-docinfo to partially override AsciiDoctor's default style sheet so that the `<code>` sections of the synopsis are no longer each rendered on their own, individual lines.

This fixes https://github.com/git-for-windows/git/issues/5063.

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
---
    asciidoctor: fix synopsis rendering
    
    This was reported in https://github.com/git-for-windows/git/issues/5063
    and has been fixed in Git for Windows already (in
    https://github.com/git-for-windows/git/pull/5064, because Git for
    Windows uses AsciiDoctor to render the HTML help pages).
    
    A related fix for https://git-scm.com/docs/ (where AsciiDoctor is used,
    too) was submitted as part of
    https://github.com/git/git-scm.com/pull/1855.
    
    This patch is based on ja/doc-markup-updates, but also applies cleanly
    to the default branch.

Published-As: https://github.com/gitgitgadget/git/releases/tag/pr-git-1749%2Fdscho%2Ffix-synopses-rendering-with-asciidoctor-v1
Fetch-It-Via: git fetch https://github.com/gitgitgadget/git pr-git-1749/dscho/fix-synopses-rendering-with-asciidoctor-v1
Pull-Request: https://github.com/git/git/pull/1749

 Documentation/Makefile     | 1 +
 Documentation/docinfo.html | 5 +++++
 2 files changed, 6 insertions(+)
 create mode 100644 Documentation/docinfo.html