Close TCPConnection on failure

[gedaiu]

I'm not sure if this is the best fix, but it looks like the TCPConnection state is connected after it fails to connect here: m_conn = connectTCP(proxyAddr, m_settings.networkInterface);

[s-ludwig]

There is a try-catch around the TLS stream construction, which seems to be the only place in the upper part of the function that can throw. It should be sufficient to put the additions into the closure at the bottom. scope (failure) is a bit problematic, though, because unfortunately it catches any Throwable as opposed to just Exception, so using an eplicit try-catch would be better here.

[gedaiu]

I found this issue on http connections, where there was no tls context. As I remember, the exception that I got was from vibe-core.