Ruby: Fix ruby reconnect/close

Once the connection is established with `c = r.connect`, and the server is restarted, You would expect `c.reconnect` to reconnect the database, but it won't. Instead it would throw an exception. Calling `c.close` also throws an exception.

This fix makes the `noreply_wait` call to ignore exceptions, and refactor `reconnect` to reuse `close` logic.