config.txt: move closing "----" to cover entire listing

Commit 1925fe0c8a ("Documentation: wrap config listings in "----"",
2019-09-07) wrapped this fairly large block of example config directives
in "----". The closing "----" ended up a few lines too early though.
Make sure to include the trailing "IncludeIf.onbranch:..." example, too.

Signed-off-by: Martin Ågren <martin.agren@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

Documentation/config.txt

@@ -220,12 +220,12 @@ Example
 ; affected by the condition
 [includeIf "gitdir:/path/to/group/"]
 	path = foo.inc
-----
 
-	; include only if we are in a worktree where foo-branch is
+; include only if we are in a worktree where foo-branch is
-	; currently checked out
+; currently checked out
-	[includeIf "onbranch:foo-branch"]
+[includeIf "onbranch:foo-branch"]
-		path = foo.inc
+	path = foo.inc
+----
 
 Values
 ~~~~~~