Fix error in dx-clone-asset when no asset project (#631)
Fix error in dx-clone-asset when no asset project (#631)

* Fix the checking of whether an asset pulling project pre-exists in the target region.
dnanexus/dx-toolkit,dnanexus/dx-toolkit,dnanexus/dx-toolkit,dnanexus/dx-toolkit,dnanexus/dx-toolkit,dnanexus/dx-toolkit,dnanexus/dx-toolkit,dnanexus/dx-toolkit