add missing punctuation

Author: Chris Cho

source/fundamentals/data-formats/pojo-customization.txt

@@ -21,7 +21,7 @@ and their properties.
 
 We show how to specify your data conversion using the :ref:`ClassModel <classmodel>`
 and :ref:`PropertyModel <property-model>` classes. You can also learn
-about more specific customization from the section on :ref:`Advanced Configuration <pojo-advanced-configuration>`
+about more specific customization from the section on :ref:`Advanced Configuration <pojo-advanced-configuration>`.
 
 We also show you how to use helpers such as :ref:`Conventions <conventions>`
 and :ref:`Annotations <annotations>` to specify common serialization actions.