doc: git-log: fix description list

b27be10 (doc: git-log: convert log config to new doc format,
2025-07-07) intended to convert a paragraph describing the different
options for `log.decorate` into a description list.  But the literal
block syntax was used by mistake.

Signed-off-by: Kristoffer Haugsbakk <code@khaugsbakk.name>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

Author: LemmingAvalanche

Documentation/config/log.adoc

@@ -23,14 +23,14 @@ be used.
 	Print out the ref names of any commits that are shown by the log
 	command. Possible values are:
 +
-----
+--
 `short`;; the ref name prefixes `refs/heads/`, `refs/tags/` and
 	`refs/remotes/` are not printed.
 `full`;; the full ref name (including prefix) are printed.
 `auto`;; if the output is going to a terminal,
 	the ref names are shown as if `short` were given, otherwise no ref
 	names are shown.
-----
+--
 +
 This is the same as the `--decorate` option of the `git log`.