Fix typo in TaskContinuationOptions.xml (#8103)

Author: cmorgan-osi

xml/System.Threading.Tasks/TaskContinuationOptions.xml

@@ -343,7 +343,7 @@
       </ReturnValue>
       <MemberValue>0</MemberValue>
       <Docs>
-        <summary>When no continuation options are specified, specifies that default behavior should be used when executing a continuation. The continuation runs asynchronously when the antecedent task completes, regardless of the antecedent's final <see cref="P:System.Threading.Tasks.Task.Status" /> property value. It the continuation is a child task, it is created as a detached nested task.</summary>
+        <summary>When no continuation options are specified, specifies that default behavior should be used when executing a continuation. The continuation runs asynchronously when the antecedent task completes, regardless of the antecedent's final <see cref="P:System.Threading.Tasks.Task.Status" /> property value. If the continuation is a child task, it is created as a detached nested task.</summary>
       </Docs>
     </Member>
     <Member MemberName="NotOnCanceled">