Allow workspace to opt-in/out of environment providers.

[edvilme]

Ussers should be able to configure their preferred environment providers (Conda, Poetry, Venv, etc) for their workspace, so that no resources are wasted looking for environments that are not relevant for their workspace.

[eleanorjboyd]

so now that we do lazy registration is this still a concern? Are you talking about at startup or when a user selects to "refresh" a re-find all environments?

[edvilme]

I think this was created before we moved conda to do lazy registration, and thus can be closed unless there is a request to explicitly "block" a certain manager