Remove unneeded cast to array

As discussed on GitHub PR #5138, $this->binds is not expected to be something else than an array.

Author: vlakoff

system/Database/Query.php

@@ -273,14 +273,13 @@ public function getOriginalQuery(): string
      */
     protected function compileBinds()
     {
-        $sql = $this->finalQueryString;
+        $sql   = $this->finalQueryString;
+        $binds = $this->binds;
 
-        if (empty($this->binds)) {
+        if (empty($binds)) {
             return;
         }
 
-        $binds = (array) $this->binds;
-
         if (is_int(array_key_first($binds))) {
             $bindCount = count($binds);
             $ml        = strlen($this->bindMarker);