unable to login using docker registry on jenkins
I think what you are doing wrong is the way you specify the credentialID to be used. 

Instead of 'awsId' try to use 'ecr:ap-southeast-1:awsId'

docker.withRegistry('https://01234.dkr.ecr.ap-southeast-1.amazonaws.com/', 'ecr:ap-southeast-1:awsId') {
    def image = docker.image("01234.dkr.ecr.ap-southeast-1.amazonaws.com/tas/master-server:${env.BUILD_ID}")
    image.push()                                        
}



EDIT: Check the plugin doc