Claim post requires a body

One of the claim's test scenario used to send `None` to the server. The
later failed to deserialize this body and the response returned 400.
This patch removes `None` from the test scenario since a body is
requires to created a claim to begin with.

Change-Id: If2c6acefc84fb2b7cc5b4a26e1784b74a1ae1e22
Closes-bug: #1383604
Merge "Claim post requires a body"