Fix typo in bats stemcell name for CentOS
Fix typo in bats stemcell name for CentOS

wcamarao/bosh-openstack-cpi-release,voelzmo/bosh-openstack-cpi-release,loewenstein/bosh-openstack-cpi-release,loewenstein/bosh-openstack-cpi-release,cloudfoundry-incubator/bosh-openstack-cpi-release,voelzmo/bosh-openstack-cpi-release,cloudfoundry-incubator/bosh-openstack-cpi-release,voelzmo/bosh-openstack-cpi-release,loewenstein/bosh-openstack-cpi-release,cloudfoundry-incubator/bosh-openstack-cpi-release,wcamarao/bosh-openstack-cpi-release,wcamarao/bosh-openstack-cpi-release