Add skeleton of 'add-default-staging-application-security-group' command

[#73577668]
Add an API object for default staging security groups

[#73577668]
Add api object to 'add-default-staging-security-group'

[#73577668]
User can add a security group to the staging default(s)

[Finishes #73577668]
Rename ApplicationSecurityGroup interface

Slightly more consistent with other repositories