Docs: fix up two XML docs

* The `HereNowdocIdentifierSpacing` one contained unescaped special chars in an attribute (oops).
* The `SpreadOperatorSpacingAfter` line length did not conform (not found via the new CI check, but even so).

Author: jrfnl

src/Standards/Generic/Docs/WhiteSpace/HereNowdocIdentifierSpacingStandard.xml

@@ -5,14 +5,14 @@
     ]]>
     </standard>
     <code_comparison>
-        <code title="Valid: No space between the <<< and the identifier string.">
+        <code title="Valid: No space between the &lt;&lt;&lt; and the identifier string.">
         <![CDATA[
 $heredoc = <em><<<EOD</em>
 some text
 EOD;
         ]]>
         </code>
-        <code title="Invalid: Whitespace between the <<< and the identifier string.">
+        <code title="Invalid: Whitespace between the &lt;&lt;&lt; and the identifier string.">
         <![CDATA[
 $heredoc = <em><<<   END</em>
 some text

src/Standards/Generic/Docs/WhiteSpace/SpreadOperatorSpacingAfterStandard.xml

@@ -25,7 +25,7 @@ function bar(<em>... </em>$spread) {
     );
 
     bar(
-        [<em>...  </em>$foo ],<em>.../*comment*/</em>array_values($keyedArray)
+        [<em>... </em>$foo ],<em>.../*@*/</em>array_values($keyed)
     );
 }
         ]]>