title: Packer not copying a file from a Linux builder machine to Windows template
body: <p>I'm using Packer to build a Windows image via a Linux build machine.
  I want to have a file copied to the image during the build process. Packer docs suggest to use <code>file provisioner</code> as per <a href="https://www.packer.io/docs/provisioners/file" rel="nofollow noreferrer">https://www.packer.io/docs/provisioners/file</a></p>
  <p>However this does not work for me. Example of my snippet:</p>
  <pre><code>        {
              &quot;type&quot;: &quot;file&quot;,
              &quot;source&quot;: &quot;/run/secrets/file.xml&quot;,
              &quot;destination&quot;: &quot;C:\\&quot;
          }
  </code></pre>
  <p>The build does not error, but when the image is provisioned, I do not see the file copied anywhere. I have used different source/dest to no avail.
  I'm not bothered where it gets copied to as I will move it later via pwsh.</p>
  <p>Not sure where I'm going wrong? Packer version 1.6.3</p>