chore: update deps and use socket.io server v4

[achingbrain]

To reduce dupes in the dep tree

• Updates all deps
• Runs client tests with socket.io-client 2, 3 and 4
• Destroys channel when handshake errors, otherwise they are left open and the tests fail to finish
• Configures v4 server to allow v2 clients to connect, removes v2 server but keeps HTTP paths the same

There are further tests that fail to finish, I think node-wrtc is failing to close connections properly so I added --exit to the test run to simulate the previous behaviour of aegir but this really needs fixing.

[vasco-santos]

this broke CI, mind having a look?

[vasco-santos]

There are further tests that fail to finish, I think node-wrtc is failing to close connections properly so I added --exit to the test run to simulate the previous behaviour of aegir but this really needs fixing.

added an issue to track it