Filtering empty params out of the query string.

This fixes errors caused by cahnges in cake 3.2.3

src/Controller/Component/PrgComponent.php

@@ -46,8 +46,16 @@ public function conversion($redirect = true)
             return null;
         }
         if ($redirect) {
+            $params = $this->request->data;
+
+            foreach ($params as $k => $param) {
+                if (is_string($param) && strlen($param) === 0) {
+                    unset($params[$k]);
+                }
+            }
+
             return $this->_registry->getController()->redirect(
-                $this->request->params['pass'] + ['?' => $this->request->data]
+                $this->request->params['pass'] + ['?' => $params]
             );
         }
         return null;

src/Model/Behavior/SearchBehavior.php

@@ -68,6 +68,11 @@ public function findSearch(Query $query, array $options)
      */
     public function filterParams($params)
     {
+        foreach ($params as $k => $param) {
+            if (is_string($param) && strlen($param) === 0) {
+                unset($params[$k]);
+            }
+        }
         return ['search' => array_intersect_key($params, $this->_getAllFilters())];
     }