add scope datasource, tests, and docs

[grantorchard]

For different configuration workflows, we need to pass the scope id in as an argument. This data source allows discovery of a scope by its name which is a smoother pattern than needing to login to the UI to discover it.

Replaces #304.

[drewmullen]

The only thing I might recommend is that in the docs explain with a info block that using this data source for the global scope is unnecessary. When I was first learning boundary I got hung up on finding out the "id" of the global scope... which is "global" lol

You could probably DRY some of the config in your test w the configs in the scope resource but that memory savings is pretty minimal

[louisruch]

LGTM

[grantorchard]

The only thing I might recommend is that in the docs explain with a info block that using this data source for the global scope is unnecessary. When I was first learning boundary I got hung up on finding out the "id" of the global scope... which is "global" lol

You could probably DRY some of the config in your test w the configs in the scope resource but that memory savings is pretty minimal

Thanks for the feedback, I've added a comment on the global scope to that effect.