set pandoc 8 character tab stops for HTML conversion

We add `--tab-stop=8` to all `pandoc(1)` executions in order to set
a better tab stop indentation, especially for tab intended code blocks.

Changed `bin/pandoc-wrapper.sh` VERSION "1.5.3 2024-03-26"
to "1.6 2024-03-31".

Fixed `1991/brnstnd/sorta.README.md` so that the sorta code
is code blocks.

Removed unneeded paragraph group in copyright in `inc/footer.default.html`.

Performed `make www` to perform the above and test under macOS.

contact.html

@@ -166,7 +166,7 @@ And while using Mastodon is free, the <a href="../judges.html">IOCCC judges</a>
 <a href="mailto:q.YYYY@ioccc.org?subject=IOCCC%20YYYY%20question%20%3C===%20You%20MUST%20change%20YYYY%20to%20the%204-digit%20year%20in%20both%20the%20To%20address%20and%20Subject,%20then%20remove%20this%20arrow%20note%20from%20the%20subject%20line!">q.YYYY@ioccc.org</a></p>
 <p><strong>IMPORTANT:</strong> The <em>YYYY</em> in the above Email address <strong>MUST</strong> be changed to the current 4 digit year!</p>
 <p>You <strong>MUST</strong> include the following two words (separated by a space) in the subject of your email, otherwise the email will be rejected:</p>
-<pre><code>IOCCC YYYY</code></pre>
+<p>IOCCC YYYY</p>
 <p><strong>IMPORTANT:</strong> The <em>YYYY</em> in the above Email address <strong>MUST</strong> be changed to the current 4 digit year!</p>
 <!--
 
@@ -174,11 +174,11 @@ And while using Mastodon is free, the <a href="../judges.html">IOCCC judges</a>
 
     You are free to share and adapt this file under the terms of this license:
 
-    Creative Commons Attribution-ShareAlike 4.0 International (CC BY-SA 4.0)
+        Creative Commons Attribution-ShareAlike 4.0 International (CC BY-SA 4.0)
 
     For more information, see:
 
-    https://creativecommons.org/licenses/by-sa/4.0/
+        https://creativecommons.org/licenses/by-sa/4.0/
 
 -->
 
@@ -215,7 +215,7 @@ And while using Mastodon is free, the <a href="../judges.html">IOCCC judges</a>
 <div class="footer">
   <h2>Copyright and CC BY-SA 4.0 License</h2>
   <p>This file and web page is:</p>
-  <blockquote><p><b>Copyright &copy; 1984-2024 by Landon Curt Noll. All Rights Reserved.</b></p></blockquote>
+  <blockquote><b>Copyright &copy; 1984-2024 by Landon Curt Noll. All Rights Reserved.</b></blockquote>
   <p>You are free to share and adapt this file under the terms of this license:</p>
   <blockquote><b>Creative Commons Attribution-ShareAlike 4.0 International (CC BY-SA 4.0)</b></blockquote>
   <p>For more information, see:</p>