REplace isahc with ureq everywhere gpui is used.
This should allow us to make http requests without libssl; and avoid a
long-tail of panics caused by ishac.
Release Notes:
- (potentially breaking change) updated our http client
---------
Co-authored-by: Mikayla <mikayla@zed.dev>
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
