[transport] Add abort support for dialing

[jacobheun]

In progress dials can cause terminating libp2p nodes to hang, https://github.com/libp2p/js-libp2p-switch/issues/281. Additionally, being able to abort in progress dials would help us better support future iterations of connection management and coalescing dials.

While the listener.close method should terminate existing connections, it does not handle closing out in progress dials. In the event a dial is taking a significant amount of time, due to connectivity or issue with the receiving node, applications can take a significant amount of time to shutdown gracefully.

[jacobheun]

This is done, all transports implementing the new interface (as of libp2p 0.27) have full support for dial aborting.