Refinement of Hole Punching Service

[diegomrsantos]

This PR incorporates several updates to the Hole Punching Service.

Key Changes:

1. The dcutr sync message doesn't send addresses anymore.

2. The dcutr server upgrades as the incoming side instead of the client. It was necessary in order to work with go-libp2p.

3. The dcutr version has been updated to exclude the version number as it is in the spec.

4. A new condition has been added during the direct connection attempt to check if an address contains the "p2p-circuit". If it does, or if an error is encountered, the function will continue without further processing.

5. The initTAddress has been fixed to not accept DNS addresses. Tests were added.

[codecov]

Codecov Report

Merging #892 (c8daec4) into unstable (225accd) will increase coverage by 0.03%.
The diff coverage is 100.00%.

Additional details and impacted files

@@             Coverage Diff              @@
##           unstable     #892      +/-   ##
============================================
+ Coverage     84.30%   84.33%   +0.03%     
============================================
  Files            91       91              
  Lines         15333    15335       +2     
============================================
+ Hits          12926    12933       +7     
+ Misses         2407     2402       -5     

Impacted Files	Coverage Δ
libp2p/multiaddress.nim	86.73% <ø> (ø)
libp2p/protocols/connectivity/dcutr/core.nim	100.00% <ø> (ø)
libp2p/wire.nim	61.84% <ø> (ø)
libp2p/protocols/connectivity/dcutr/client.nim	86.95% <100.00%> (+10.86%)	⬆️
libp2p/protocols/connectivity/dcutr/server.nim	72.72% <100.00%> (ø)
libp2p/services/hpservice.nim	87.17% <100.00%> (+0.33%)	⬆️