title: Process XML message using PostAsync from IHttpClientFactory
body: <p>I had a problem to process soapEnvelopeXml document using <strong>PostAsync</strong> method from <strong>IHttpClientFactory</strong>.
  This is what I was trying to do :</p>
  <pre><code>var soapEnvelopeXml = ObjectToXMLDocumentConverter.ObjectAsXmlDocument(object);
  var content = new StringContent(soapEnvelopeXml.ToString(), Encoding.UTF8, &quot;text/xml&quot;);
  var response = await client.PostAsync(endpoint, content);
  </code></pre>
  <p>This was producing 400 Bad Request error.</p>