Update changes/5.3.rst to mention fix of #6740

Close #6740.

Author: jfbu

doc/changes/5.3.rst

@@ -8,7 +8,10 @@ Release 5.3.0 (released Oct 16, 2022)
 
 * #10759: LaTeX: add :confval:`latex_table_style` and support the
   ``'booktabs'``, ``'borderless'``, and ``'colorrows'`` styles.
-  (thanks to Stefan Wiehler for initial pull requests #6666, #6671)
+  (thanks to Stefan Wiehler for initial pull requests #6666, #6671).
+  Using the ``'booktabs'`` style solves #6740 (Removing LaTeX
+  column borders for automatic colspec).
+  Patch by Jean-François B.
 * #10840: One can cross-reference including an option value like
   ``:option:`--module=foobar```, ``:option:`--module[=foobar]```,
   or ``:option:`--module foobar```.