resolves #115 export getDefaultCommand on converter for exporter to supply default command
<span class="gl-align-middle -gl-mr-2 has-tooltip" title="The source project is a fork"><svg class="s12 gl-ml-1 has-tooltip" data-testid="fork-icon"><use href="/assets/icons-41229992eca580608aadaaa9b83b717650b2863442574d0ebb87f859c42a3b6c.svg#fork"></use></svg></span> opendevise/forks/antora-assembler:issue-115-get-default-command into main