remove redundant nil-check in the packet packer

[q191201771]

No description provided.

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[codecov]

Codecov Report

Merging #3048 (d16f36a) into master (bfad411) will increase coverage by 0.03%.
The diff coverage is n/a.

@@            Coverage Diff             @@
##           master    #3048      +/-   ##
==========================================
+ Coverage   86.17%   86.20%   +0.03%     
==========================================
  Files         132      132              
  Lines        9352     9350       -2     
==========================================
+ Hits         8059     8060       +1     
+ Misses        936      934       -2     
+ Partials      357      356       -1     

Impacted Files	Coverage Δ
packet_packer.go	84.65% <ø> (+0.35%)	⬆️
internal/utils/rand.go	75.00% <0.00%> (+12.50%)	⬆️

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[marten-seemann]

@q191201771 Can you please sign the CLA? This is a requirement for merging this PR.

[q191201771]

@googlebot I signed it!

[googlebot]

CLAs look good, thanks!

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