Moves `cloud_api_client` off the `zed-industries/yawc` fork pin
(`71a452f`) to the upstream crates.io release, `yawc` 0.4.2.

The fork's only commit beyond upstream was an earlier version of a wasm
connect fix. Upstream shipped a more complete fix in 0.4.0
([infinitefield/yawc@f1c6317](https://github.com/infinitefield/yawc/commit/f1c6317eff64a01433aad683280e22ddff4f9c3f)):

- `connect` settles on the browser's `open`, `error`, or `close` event.
- The wasm `WebSocket` owns its event handlers instead of leaking them
with `Closure::forget`.
- `Drop` unregisters the handlers and calls `close()`, including when
the connect future is dropped mid-handshake.

That last point matters for the web Cloud client, which drops a pending
connect after 30 seconds. With the fork, the abandoned browser socket
kept handshaking indefinitely. Delta hit the same leak in its web client
and has already moved to 0.4.2.

The other changes between the fork and 0.4.2 are native-only: opt-in
HTTP/2 WebSockets, SOCKS5 proxy support, and a deflate decompression
fix. The APIs `cloud_api_client` uses are unchanged. The lock file also
picks up `send_wrapper` and bumps `hyper` to 1.11 and `h2` to 0.4.19,
which `yawc` 0.4.2 requires.

Checked with `cargo check -p cloud_api_client` for native and
`wasm32-unknown-unknown`.

Release Notes:

- N/A