Ported mocha templatedata.js to phpunit TemplateDataTest.php

* Found an issue with WikitestSerializer where under test
  conditions of new content, NoFormatWithParamOrder it accesses
  $tplData['params'] which are not set causing a crash. I
  removed $params as a seperate variable and allow the merged
  $aliases = $tplData['params'][$key]['aliases'] ?? [];
  to define an empty array if it is not set.

Bug: T237693
Change-Id: I802444e426bd6819bcd628a26ce93cd48b6af1f7

src/Html2Wt/WikitextSerializer.php

@@ -614,13 +614,12 @@ private function createParamComparator(
 		$aliasMap = [];
 		$keys = [];
 		if ( $tplData && isset( $tplData['paramOrder'] ) ) {
-			$params = $tplData['params'];
 			foreach ( $tplData['paramOrder'] as $i => $key ) {
 				$tplDataOrder[$key] = [ 'order' => $i ];
 				$aliasMap[$key] = [ 'key' => $key, 'order' => -1 ];
 				$keys[] = $key;
 				// Aliases have the same sort order as the main name.
-				$aliases = $params[$key]['aliases'] ?? [];
+				$aliases = $tplData['params'][$key]['aliases'] ?? [];
 				foreach ( $aliases as $j => $alias ) {
 					$aliasMap[$alias] = [ 'key' => $key, 'order' => $j ];
 				}