AB-namespace-delete-012

The pipeline

<p:declare-step xmlns:err="http://www.w3.org/ns/xproc-error"
                xmlns:p="http://www.w3.org/ns/xproc"
                xmlns:t="http://xproc.org/ns/testsuite/3.0" version="3.0">
   <p:output port="result"/>
   <p:namespace-delete xmlns:other="http://other"
                       xmlns:pre="http://something" prefixes="pre other">
      <p:with-input>
         <document>
            <element other:att="3" pre:att="4"/>
         </document>
      </p:with-input>
   </p:namespace-delete>
</p:declare-step>