fix: MockResult::dataSeek() return type

Author: kenjis

system/Database/OCI8/Result.php

@@ -13,6 +13,7 @@
 
 use CodeIgniter\Database\BaseResult;
 use CodeIgniter\Entity\Entity;
+use stdClass;
 
 /**
  * Result for OCI8

system/Test/Mock/MockResult.php

@@ -63,6 +63,7 @@ public function freeResult()
      */
     public function dataSeek($n = 0)
     {
+        return true;
     }
 
     /**