dlipovetsky: feat: Create bastion security group only when bastion is enabled

JobBuild
3482
05-18 17:51
pull-cluster-api-provider-aws-apidiff-main 1526983831737864192
pull-cluster-api-provider-aws-build 1531722025997963264 1526983831771418624
pull-cluster-api-provider-aws-test 1531722025960214528 1526983831704309760
pull-cluster-api-provider-aws-verify 1531722026035712000 1526983831800778752