provisioner/shell: fix dropped test error
provisioner/shell: fix dropped test error

rnaveiras/packer,pecigonzalo/packer,rnaveiras/packer,rnaveiras/packer,hashicorp/packer,mitchellh/packer,grubernaut/packer,ricardclau/packer,ricardclau/packer,pecigonzalo/packer,rnaveiras/packer,hashicorp/packer,grubernaut/packer,hashicorp/packer,rnaveiras/packer,pecigonzalo/packer,grubernaut/packer,rnaveiras/packer,ricardclau/packer,mitchellh/packer,pecigonzalo/packer,grubernaut/packer,grubernaut/packer,ricardclau/packer,mitchellh/packer,mitchellh/packer,ricardclau/packer,mitchellh/packer,grubernaut/packer,hashicorp/packer,ricardclau/packer