Fix where clause binding access issue

Author: mikebronner

src/CacheKey.php

@@ -129,7 +129,7 @@ protected function getValuesFromWhere(array $where) : string
 
     protected function getValuesFromBindings(array $where, string $values) : string
     {
-        if (! $values && ($this->query->bindings["where"] ?? false)) {
+        if (! $values && ($this->query->bindings["where"][$this->currentBinding] ?? false)) {
             $values = $this->query->bindings["where"][$this->currentBinding];
             $this->currentBinding++;