Update module github.com/pion/stun/v3 to v3.0.0

Prevent heap allocations in FiveTuple Fingerprint

Prevent heap allocations in FiveTuple Fingerprint

Support stand alone STUN server mode

Running in stand alone STUN server does not start
due to packet conn config requiring relay address config
during validation.

To enable that mode, bypass validation if relay address config
in packet conn config is nil.

Note that it is still validated in `ListenerConfig`.

Use signed timestamp for nonce

Fix out of bounds access panic

Drop packet exceeding size of input buffer.

Update module github.com/pion/stun to v2

Generated by renovateBot

Start pion/turn@v3

This is required to update pion/transport/v2 to v3

The public API of transport changed, and we expose transport as part of
our public API.

Update AUTHORS.txt

Partial revert of 79fbb4e

This commit broke public API, this reverts those changes

Resolves #339