message: Use ensureSessionClosed.
diff: @@ -250,10 +250,8 @@ export class RpcSessions implements Disposable {
  }
  ensureAllSessionsClosed() {
  - this.#connected.forEach(rs => rs.dispose())
  - this.#connecting.forEach(fut => fut.then(rs => rs?.dispose()))
  - this.#connected.clear()
  - this.#connecting.clear()
  + [...this.#connected.keys()].forEach(uri => this.ensureSessionClosed(uri));
  + [...this.#connecting.keys()].forEach(uri => this.ensureSessionClosed(uri));
  }
  dispose() {
  