fix(Felamimail/Vacation): fix html vacation

... as this created visible html elements in vacation messages

tine20/Felamimail/Sieve/Vacation.php

@@ -332,9 +332,7 @@ protected function _getFormattedHTMLBody(string $reason): string
         $doc = new DOMDocument('1.0', 'UTF-8');
         $doc->preserveWhiteSpace = true;
         $doc->formatOutput = true;
-        $html = $doc->createElement('html');
-        $html->appendChild($doc->createElement('body', $reason));
-        $doc->appendChild($html);
+        $doc->loadHTML('<?xml version="1.0" encoding="utf-8"?>' . $reason);
         $doc->saveXML();
         $xpath = new DOMXPath($doc);
         $bodyNodes = $xpath->query('/html/body')->item(0)->childNodes;
@@ -344,7 +342,7 @@ protected function _getFormattedHTMLBody(string $reason): string
         }
         return implode(PHP_EOL, $outputFragments);
     }
-    
+
     /**
      * quote string for usage in Sieve script 
      *