Support for HTTP Basic authentication in HTTP and WebSocket RPC clients

[romac]

Version(s) of tendermint-rs:

Summary

Add support for HTTP Basic authentication in HTTP and WebSocket RPC clients.

Problem definition

On the Hermes, we have heard a request from some operators to allow them to connect to a full node protected by HTTP Basic authentication.

We initially thought that simply embedding the username and password in the RPC/WebSocket URL (eg. http://username:password@example.com:1234) would work but it does not.

It seems like hyper does not automatically parse and use the username/password embedded in the URL. Instead, we have to manually add an Authorization header to the request.

Same thing with (async-)tungstenite, we have to manually set the Authorization header when building the initial HTTP request that upgrades the connection to WebSocket.

Proposal

Implement support for HTTP Basic authentication for the HTTP and WebSocket clients in tendermint-rpc.

Acceptance criteria

1. Both the HTTP and WebSocket clients can connect to a node protected by HTTP Basic authentication.
2. Hermes can connect to a node protected by HTTP Basic authentication. See how to reproduce this on the linked issue.

[thanethomson]

Closed by #1170