Users of our http_client crate knew they were interacting with isahc as
they set its extensions on the request. This change adds our own
equivalents for their APIs in preparation for changing the default http
client.
Release Notes:
- N/A
This PR adds a registry for `GitHostingProvider`s.
The intent here is to help decouple these provider-specific concerns
from the lower-level `git` crate.
Similar to languages, the Git hosting providers live in the new
`git_hosting_providers` crate.
This work also lays the foundation for if we wanted to allow defining a
`GitHostingProvider` from within an extension. This could be useful if
we wanted to extend the support to work with self-hosted Git providers
(like GitHub Enterprise).
I also took the opportunity to move some of the provider-specific code
out of the `util` crate, since it had leaked into there.
Release Notes:
- N/A
