Add MemoryDataStream::reset() method

[mikee47]

The class already has a clear() method but this leaves existing memory allocated. The purpose is to allow re-use of an existing class instance efficiently by reducing memory reallocations.

The new reset() method allows the instance to be cleared and also release allocated memory. The new name is consistent with std::unique_ptr::reset() usage.

A similar thing can be accomplished by using std::unique_ptr<MemoryDataStream> however an in-built reset() method makes for cleaner code.

[what-the-diff]

PR Summary

• Addition of reset Function to MemoryDataStream Class
  This update introduces a new feature called reset in the MemoryDataStream class. The purpose of this function is to clear the stream and free up any memory that was being used, improving performance and potentially preventing any system slowdown due to excessive memory consumption. This change enhances the functionality and efficiency of our system.