fix retry key and nonce for draft-34

[marten-seemann]

Fortunately, we haven't cut any release that officially supports draft-34 yet.

[codecov]

Codecov Report

Merging #3062 (bd172b2) into master (2c45f2b) will increase coverage by 0.01%.
The diff coverage is 100.00%.

@@            Coverage Diff             @@
##           master    #3062      +/-   ##
==========================================
+ Coverage   86.16%   86.16%   +0.01%     
==========================================
  Files         132      132              
  Lines        9355     9360       +5     
==========================================
+ Hits         8060     8065       +5     
  Misses        938      938              
  Partials      357      357              

Impacted Files	Coverage Δ
internal/handshake/retry.go	75.00% <100.00%> (+6.58%)	⬆️
server.go	82.25% <100.00%> (ø)
session.go	77.78% <100.00%> (ø)

---

Continue to review full report at Codecov.

Legend - Click here to learn more
Δ = absolute <relative> (impact), ø = not affected, ? = missing data
Powered by Codecov. Last update 2c45f2b...bd172b2. Read the comment docs.

[marten-seemann]

The interop runner is happy with these changes.