fix TransChoiceTokenParser deprecation message

Author: fbourigault

TokenParser/TransChoiceTokenParser.php

@@ -40,7 +40,7 @@ public function parse(Token $token)
         $lineno = $token->getLine();
         $stream = $this->parser->getStream();
 
-        @trigger_error(sprintf('The "transchoice" tag is deprecated since Symfony 4.2, use the "trans" one instead with a "%count%" parameter in %s line %d.', $stream->getSourceContext()->getName(), $lineno), E_USER_DEPRECATED);
+        @trigger_error(sprintf('The "transchoice" tag is deprecated since Symfony 4.2, use the "trans" one instead with a "%%count%%" parameter in %s line %d.', $stream->getSourceContext()->getName(), $lineno), E_USER_DEPRECATED);
 
         $vars = new ArrayExpression(array(), $lineno);