This change removes [Activate] from ViewComponents. Accessing context
should be done through [ViewComponentContext]. Accessing services should
be done though constructor injection.
These tests verify that per-request services can be injected into assets
that users provide/implements (filters, constraints, controllers, views,
etc).
The purpose is to verify that the services are correctly resolved from the
per-request service container, and don't have state that lingers and
influences the next request. This is important because changing the
lifetime of a framework services could easily impact the lifetimes of
others, and ultimately of something the user created.