Opensearch: Fixed XML declaration when php short tags enabled

For #5673

Author: ssddanbrown

resources/views/misc/opensearch.blade.php

@@ -1,4 +1,4 @@
-<?xml version="1.0" encoding="UTF-8"?>
+@php echo '<?xml version="1.0" encoding="UTF-8"?>' . "\n"; @endphp
 <OpenSearchDescription xmlns="http://a9.com/-/spec/opensearch/1.1/">
   <ShortName>{{ mb_strimwidth(setting('app-name'), 0, 16) }}</ShortName>
   <Description>{{ trans('common.opensearch_description', ['appName' => setting('app-name')]) }}</Description>

tests/Meta/OpensearchTest.php

@@ -15,6 +15,7 @@ public function test_opensearch_endpoint()
 
         $resp = $this->get('/opensearch.xml');
         $resp->assertOk();
+        $resp->assertSee('<?xml version="1.0" encoding="UTF-8"?>' . "\n", false);
 
         $html = $this->withHtml($resp);