add (rust-libp2p) gossipsub over WebRTC to interop tests

[DougAnderson444]

I'm not exactly sure where to open this issue, as I also see a repo for interop tests over here: https://github.com/libp2p/interop . If I've missed where this test is, my appologies.

Right now we are seeing some connectivity challenges within rust-libp2p operating over WebRTC transport to the browser.

See

• bug(Gossipsub over WebRTC) Unpredictable Dial upgrade Timeout error rust-libp2p#3665

Work is being done to demonstrate the universal connectivity amongst libp2p implementations:

• Rust server universal-connectivity#3

Fixes for these issues are in the works, such as:

• fix(gossipsub): gracefully disable handler on stream errors rust-libp2p#3625

I'm looking for interop tests for this to streamline troubleshooting and development, but have not found any to support this yet. This issue proposes an interop test, particularly for Gossipsub over WebRTC between rust and js, as it's in active troubleshooting at the moment.

It appears the interop tests for pubsub cover js and go:

https://github.com/libp2p/interop/blob/ce0aa3749c9c53cf5ad53009b273847b94106d40/src/pubsub/gossipsub.ts#L8-L9

export function gossipsubTests (factory: DaemonFactory) {
  const nodeTypes: NodeType[] = ['js', 'go']

but I am having a hard time finding the test where each of the different transports are used.