Consider renaming `ReceiverStoppedError` to `ReceiverClosedError`

[llucax]

What's needed?

Now that receivers have the close() method, it feels a bit asymmetric to have an exception with Stopped instead of Closed.

Proposed solution

• Rename ReceiverStoppedError to
• Add a deprecated alias for ReceiverClosedError named ReceiverStoppedError (to keep backwards compatibility)
• Remove the deprecated alias in v2