fix list item termination character

Author: xabbuh

contributing/code/standards.rst

@@ -173,7 +173,7 @@ Structure
 
 * Calls to :phpfunction:`trigger_error` with type ``E_USER_DEPRECATED`` must be
   switched to opt-in via ``@`` operator.
-  Read more at :ref:`contributing-code-conventions-deprecations`.
+  Read more at :ref:`contributing-code-conventions-deprecations`;
 
 * Do not use ``else``, ``elseif``, ``break`` after ``if`` and ``case`` conditions
   which return or throw something.