Removing defunct 'encloses' definition (#3636)

Closes #3510

The definition of "Encloses" was in the draft normative text for Focus
Appearance, but was removed before publication. Therefore there is no
normative content that uses this term, and it is being removed.


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guidelines/index.html

@@ -622,8 +622,6 @@ <h1>Glossary</h1>
 
                 <dt data-include="terms/20/emergency.html" data-include-replace="true"></dt>
 
-                <dt data-include="terms/22/encloses.html" data-include-replace="true"></dt>
-
               	<dt data-include="terms/20/essential.html" data-include-replace="true"></dt>
 
                 <dt data-include="terms/20/extended-audio-description.html" data-include-replace="true"></dt>