[303] Md5HashListProvider does not allocate extra byte array when calculating a buffer's hash list

[giventocode]

Closes: #303

This PR includes:

• Removes the unnecessary/extra allocation of a byte array when creating a hash list of a pipeline buffer.
  • This was the root cause of Runner consumes too much memory when uploading a large file #303, as it resulted in the significant increase of the LOH size.