[BUGFIX] Infinite loop in SolrRoutingMiddleware #3873

Fixes infinite loop and therefore server crashing if route doesn't exist or URl is in the scheme like domain/id=123456

Fixes: #3873
Ports: #3878

Classes/Middleware/SolrRoutingMiddleware.php

@@ -336,7 +336,7 @@ protected function retrievePageInformation(UriInterface $uri, Site $site): array
 
                 if ($scan) {
                     $elements = explode('/', $path);
-                    if (empty($elements)) {
+                    if (empty($elements) || $path === '') {
                         $scan = false;
                     } else {
                         array_pop($elements);