Add e2e test coverage for non-HTTP traffic

[haiyanmeng]

https://github.com/agent-substrate/substrate/blob/9bfc67e8159993fce4f120e3a561a7ee61495959/internal/e2e/suites/networking/networking_test.go has test coverage for HTTP and HTTPS traffic: TestActorEgress and TestActorEgressHTTPS.

We should add e2e test coverage for non-HTTP traffic, such as running git clone git@github.com:agent-substrate/substrate.git from an actor.

The test coverage gap was identified during the review process of #871.

cc Bowei Du (@bowei) Lior Lieberman (@LiorLieberman)

[haiyanmeng]

#1024 adds test coverage for SSH traffic

I plan to add e2e test coverage for WebSockets and SSE today.

Are there other types of traffic we need to cover? Bowei Du (@bowei) Lior Lieberman (@LiorLieberman)

[bowei]

We can add to fill out the matrix. I do not expect everything to pass:

(All HTTP variants should be tested with HTTP/1.1, HTTP/2, HTTP/3)
(All protocols should be tested against IPv4, IPv6)

• TCP ping/pong, client-initiated
  • e2e: cover egress for raw TCP and SSH traffic, in both speaking orders #1024
• TCP pong/ping, client connects, server sends data first
  • e2e: cover egress for raw TCP and SSH traffic, in both speaking orders #1024
• GRPC request / response
• GRPC bi-di streaming
• {HTTP,HTTPS} on standard port
  • TestActorEgressHTTP and TestActorEgressHTTPS
• HTTP/1.1 on non-80 port
• HTTPS/1.1 on non-443 port
• HTTP upgrade to WebSocket
  • haiyanmeng is working on this
• HTTPS upgrade to WebSocket
• HTTP CONNECT (Actor itself initiates a CONNECT)
• HTTPS CONNECT (Actor itself initiates a CONNECT)
• HTTP/3 QUIC plaintext
• HTTP/3 QUIC encrypted
• UDP ping/pong
• SSH protocol
  • e2e: cover egress for raw TCP and SSH traffic, in both speaking orders #1024
• DNS
• mysql protocol