move the DisableVersionNegotiationPackets flag to the Transport

[marten-seemann]

Small API cleanup. This flag makes more sense on the Transport than on the Config, since this is not a per-connection option.

It's probably easiest to review this PR without whitespace changes: https://github.com/quic-go/quic-go/pull/4047/files?diff=unified&w=1

[codecov]

Codecov Report

Merging #4047 (180b5e1) into master (e058f56) will increase coverage by 0.04%.
The diff coverage is 94.83%.

@@            Coverage Diff             @@
##           master    #4047      +/-   ##
==========================================
+ Coverage   83.31%   83.35%   +0.04%     
==========================================
  Files         147      147              
  Lines       14908    14907       -1     
==========================================
+ Hits        12420    12425       +5     
+ Misses       1988     1985       -3     
+ Partials      500      497       -3     

Files Changed	Coverage Δ
interface.go	0.00% <ø> (ø)
transport.go	72.31% <84.21%> (+3.81%)	⬆️
config.go	100.00% <100.00%> (ø)
server.go	75.93% <100.00%> (+0.04%)	⬆️

... and 2 files with indirect coverage changes