Respect checksum header over setting

[TingDaoK]

Issue #, if available:

• we allow user to set checksum config from either the meta_request_options or implicitly from the header of the http request.
• The config from the meta_request_options previously takes precedence before this PR.
• If we keep the same trailing checksum config from meta_request_options for both multipart and single part upload and full object checksum from header
  • in the case of single part upload, we will have both trailer checksum and the header checksum, which will lead to an error
  • in the case of multipart upload, the parts level checksum will be added, and the full object checksum will be applied to the complete MPU, which will be the expected behavior.
• In order to make it consistent, we now takes the header config over the meta_request_options config. So that we will ignore any settings from the meta request options and prefer the implicitly one from the header and make sure they land in the expected behavior.

Description of changes:

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