The 'nunit3-junit.xslt' is not transform skipped test case correctly.

[watsonsong]

If a test suite with some test case skipped, the nunit report xml will contains:

<test-suite>
  <reason>
    <message><![CDATA[One or more child tests were ignored]]></message>
  </reason>
  <test-case>
    <reason>
      <message><![CDATA[]]></message>
    </reason>
  </test-case>
</test-suite>

The passed test-case will produce reason with empty message, but transform to junit, the test case will marked as skipped:

<testcase>
  <skipped message="" />
</testcase>

https://github.com/nunit/nunit-transforms/pull/22