fix typo in doc of alicloud
fix typo in doc of alicloud

dave2/packer,mitchellh/packer,grubernaut/packer,youhong316/packer,rnaveiras/packer,bryson/packer,paulmey/packer,tas50/packer,dave2/packer,grubernaut/packer,paulmey/packer,paulmey/packer,mitchellh/packer,rnaveiras/packer,tas50/packer,tas50/packer,mkuzmin/packer,timsutton/packer,ricardclau/packer,mitchellh/packer,hashicorp/packer,ricardclau/packer,timsutton/packer,timsutton/packer,bryson/packer,pecigonzalo/packer,mkuzmin/packer,paulmey/packer,youhong316/packer,ricardclau/packer,dave2/packer,youhong316/packer,timsutton/packer,ricardclau/packer,timsutton/packer,bryson/packer,dave2/packer,grubernaut/packer,pecigonzalo/packer,paulmey/packer,ricardclau/packer,pecigonzalo/packer,mkuzmin/packer,tas50/packer,ricardclau/packer,youhong316/packer,paulmey/packer,youhong316/packer,grubernaut/packer,tas50/packer,rnaveiras/packer,dave2/packer,mkuzmin/packer,rnaveiras/packer,bryson/packer,mkuzmin/packer,youhong316/packer,dave2/packer,rnaveiras/packer,hashicorp/packer,bryson/packer,bryson/packer,mitchellh/packer,rnaveiras/packer,mkuzmin/packer,mitchellh/packer,hashicorp/packer,grubernaut/packer,grubernaut/packer,tas50/packer,timsutton/packer,hashicorp/packer,pecigonzalo/packer