Drop compat code for pre-MW-36 (#821)

Author: JeroenDeDauw

src/Presentation/WikitextParser.php

@@ -23,7 +23,7 @@ public function wikitextToHtml( string $text ): string {
 		return $this->parser->parse(
 			$text,
 			$this->parser->getTitle(),
-			new ParserOptions( method_exists( $this->parser, 'getUserIdentity' ) ? $this->parser->getUserIdentity() : $this->parser->getUser() )
+			new ParserOptions( $this->parser->getUserIdentity() )
 		)->getText();
 	}