Fix retrieval of bodies larger than the large object heap but below the maximum body size to store

[danielmarbach]

Fixes regression introduced in #1843

            private static readonly byte[] body = Encoding.UTF8.GetBytes($@"<?xml version=""1.0""?>
<MyMessage xmlns:xsi=""http://www.w3.org/2001/XMLSchema-instance"" xmlns:xsd=""http://www.w3.org/2001/XMLSchema""
            xmlns=""http://tempuri.net/"">
   <MyProperty>{new string('a', 87 * 1024)}</MyProperty>
</MyMessage>");

Before

After

[WilliamBZA]

When_processed_message_is_imported.Should_be_accessible_via_the_rest_api is failing now

[danielmarbach]

@WilliamBZA just pushed a fix