Add annotation aws-load-balancer-security-groups

Author: jorge-gasca

content/en/docs/concepts/cluster-administration/cloud-providers.md

@@ -99,6 +99,7 @@ Different settings can be applied to a load balancer service in AWS using _annot
 * `service.beta.kubernetes.io/aws-load-balancer-connection-draining-timeout`: Used on the service to specify a connection draining timeout.
 * `service.beta.kubernetes.io/aws-load-balancer-connection-idle-timeout`: Used on the service to specify the idle connection timeout.
 * `service.beta.kubernetes.io/aws-load-balancer-cross-zone-load-balancing-enabled`: Used on the service to enable or disable cross-zone load balancing.
+* `service.beta.kubernetes.io/aws-load-balancer-security-groups`: Used to specify the security groups to be added to ELB created. This replaces all other security groups previously assigned to the ELB.
 * `service.beta.kubernetes.io/aws-load-balancer-extra-security-groups`: Used on the service to specify additional security groups to be added to ELB created
 * `service.beta.kubernetes.io/aws-load-balancer-internal`: Used on the service to indicate that we want an internal ELB.
 * `service.beta.kubernetes.io/aws-load-balancer-proxy-protocol`: Used on the service to enable the proxy protocol on an ELB. Right now we only accept the value `*` which means enabling the proxy protocol on all ELB backends. In the future we could adjust this to allow setting the proxy protocol only on certain backends.