chore: Fix several style lints (#17488)

It's not comprehensive enough to start linting on `style` group, but
hey, it's a start.

Release Notes:

- N/A

crates/collab/src/tests/test_server.rs

@@ -263,8 +263,7 @@ impl TestServer {
                 })
             });
 
-        let git_hosting_provider_registry =
-            cx.update(|cx| GitHostingProviderRegistry::default_global(cx));
+        let git_hosting_provider_registry = cx.update(GitHostingProviderRegistry::default_global);
         git_hosting_provider_registry
             .register_hosting_provider(Arc::new(git_hosting_providers::Github));