Restore HTTP client transition, but use reqwest everywhere (#19055)

Release Notes:

- N/A

crates/gpui/src/app.rs

@@ -1533,4 +1533,8 @@ impl HttpClient for NullHttpClient {
     fn proxy(&self) -> Option<&http_client::Uri> {
         None
     }
+
+    fn type_name(&self) -> &'static str {
+        type_name::<Self>()
+    }
 }

crates/gpui/src/app/test_context.rs

@@ -431,7 +431,7 @@ impl TestAppContext {
         rx
     }
 
-    /// Retuens a stream of events emitted by the given Model.
+    /// Returns a stream of events emitted by the given Model.
     pub fn events<Evt, T: 'static + EventEmitter<Evt>>(
         &mut self,
         entity: &Model<T>,