Format fixes in html files of 2013

2013/cable1/README.md

@@ -69,20 +69,17 @@ Why late? Because:
  alt="image of snarky tweet from 2013 Nov 15 by Landon Noll about Microsoft"
  width=491 height=312>
 
-```
-    An important 2023 update about twitter:
-
-    The IOCCC no longer uses twitter.  Today the IOCCC uses Mastodon.
-    For more information and to see our IOCCC Mastodon posts, see:
-
-        https://fosstodon.org/@ioccc
-
-    End of important 2023 update to this historic note.
-```
-
 So how does a one line C source know so much?  Hint: it doesn't.
 
 
+### An important 2023 update about twitter:
+
+
+The IOCCC no longer uses twitter.  Today the IOCCC uses Mastodon.  For more
+information and to see our IOCCC Mastodon posts, see:
+<https://fosstodon.org/@ioccc>.
+
+
 ## Author's remarks:
 
 ### Presidents of the United States of America!