Hardcode AMI for us-east-2 and eu-west-3 regions for Cloud-Base
    
    Fedmsg topic 'org.fedoraproject.prod.fedimg.image.upload'
    doesn't have AMI information for these two regions. We have
    made AMIs available for these regions. So, hardcode these AMIs
    for F28 Cloud-Base
    
    Signed-off-by: Sinny Kumari <sinny@redhat.com>