fix add <cstdint> to datastructures/queue_using_array.cpp

Author: realstealthninja

data_structures/queue_using_array.cpp

@@ -18,6 +18,7 @@
  * @author [Farbod Ahmadian](https://github.com/farbodahm)
  */
 #include <array>     /// for std::array
+#include <cstdint>   /// for integral typedefs
 #include <iostream>  /// for io operations
 
 constexpr uint16_t max_size{10};  ///< Maximum size of the queue