SDL: wikiheaders: Allow markdown in the wikipreamble string.

SDL Commits
1 
From 726d6f94225c96d1764de5a43c105aba085b7a7d Mon Sep 17 00:00:00 2001
From: "Ryan C. Gordon" <[EMAIL REDACTED]>
Date: Thu, 26 Jan 2023 10:19:23 -0500
Subject: [PATCH] wikiheaders: Allow markdown in the wikipreamble string.

Reference Issue #6568.
---
 build-scripts/wikiheaders.pl | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/build-scripts/wikiheaders.pl b/build-scripts/wikiheaders.pl
index 79214c2ca212..e9793d4744d5 100755
--- a/build-scripts/wikiheaders.pl
+++ b/build-scripts/wikiheaders.pl
@@ -1169,10 +1169,11 @@ sub usage {
         $$sectionsref{'[footer]'} = $footer;
 
         if (defined $wikipreamble) {
+            my $wikified_preamble = wikify($wikitype, $wikipreamble);
             if ($wikitype eq 'mediawiki') {
-                print FH "====== $wikipreamble ======\n";
+                print FH "====== $wikified_preamble ======\n";
             } elsif ($wikitype eq 'md') {
-                print FH "###### $wikipreamble\n";
+                print FH "###### $wikified_preamble\n";
             } else { die("Unexpected wikitype '$wikitype'\n"); }
         }