In #2289 we made it easier to use an existing resource group when using a template that targets resource group scope. The question becomes, what, if any, validation do we want to preform when a user selects and existing resource group to use for their deployment?

For example, do we want to ensure that it is tagged with azd-env-name and if it is not, do something? If so, are we going to need to support the case where a single resource group is used for two azd environments, and if so, how does that play into tagging?

In practice, I do not think we need this tag for functional correctness, because we will have the name of the resource group we are targeting in the environment, and we can statically discovery it instead of trying to find it as we must for subscription based deployments.

Some discussion here: #2289 (review)

Opening this issue to track any changes we want to make here. @savannahostrowski this might tie in to some of our integrations with Starshot and others.