Implement changes to the XML documentation asked during review

WordPress/Docs/WP/GetMetaFunctionSingleParameterStandard.xml

@@ -5,23 +5,24 @@
     >
     <standard>
     <![CDATA[
-When calling the get_(comment|post|site|term|user)_meta(), get_metadata(), get_metadata_default(),
-and get_metadata_raw() functions, if the $meta_key/$key parameter is passed, the $single parameter
-should be passed as well to make it explicit what is the expected return type.
+    When calling the `get_(comment|post|site|term|user)_meta()`, `get_metadata()`,
+    `get_metadata_default()`, and `get_metadata_raw()` functions, if the `$[meta_]key` parameter is
+    passed, the `$single` parameter should be passed as well to make it explicit what is the
+    expected return type.
     ]]>
     </standard>
     <code_comparison>
-        <code title="Valid: get meta functions used with or without both $meta_key/$key and $single parameters.">
+        <code title="Valid: Get meta functions called either without the `$[meta_]key` parameter or with both the `$[meta_]key` and the `$single` parameters.">
         <![CDATA[
 $admin_color = get_user_meta(
     $user_id,
-    <em>'admin_color',
-    true</em>
+    <em>'admin_color'</em>,
+    <em>true</em>
 );
 $post_meta = get_metadata( 'post', $post_id<em></em> );
         ]]>
         </code>
-        <code title="Invalid: get meta function used with $meta_key/$key parameter and without $single parameter.">
+        <code title="Invalid: Get meta function called with the `$[meta_]key` parameter and without `$single` parameter.">
         <![CDATA[
 $admin_color = get_user_meta(
     $user_id,