Update CurlHttpClient to handle body in DELETE requests

[amzn-adrian]

Issue #, if available: None

Description of changes: The current implementation of the CurlHttpClient does not handle DELETE requests that have a body, resulting in an inconsistent behavior between CurlHttpClient and other clients in the SDK that support it. This change enables attaching a body to the request, if present.

Check all that applies:

• [X] Did a review by yourself.
• [ ] Added proper tests to cover this PR. (If tests are not applicable, explain.) Tested manually by creating DELETE requests with and without body and sending them to a server using CurlHttpClient .
• [X] Checked if this PR is a breaking (APIs have been changed) change.
• [X] Checked if this PR will not introduce cross-platform inconsistent behavior.
• [X] Checked if this PR would require a ReadMe/Wiki update.

Check which platforms you have built SDK on to verify the correctness of this PR.

• [ ] Linux
• [ ] Windows
• [ ] Android
• [X] MacOS
• [ ] IOS
• [ ] Other Platforms

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