payload: treat zero-length headers as error

[roman-khimov]

See neo-project/neo#2259.

[codecov]

Codecov Report

Merging #1716 (eecd71a) into master (aad2b3a) will increase coverage by 2.74%.
The diff coverage is 100.00%.

@@            Coverage Diff             @@
##           master    #1716      +/-   ##
==========================================
+ Coverage   79.60%   82.35%   +2.74%     
==========================================
  Files         255      255              
  Lines       21242    21245       +3     
==========================================
+ Hits        16910    17496     +586     
+ Misses       3216     2652     -564     
+ Partials     1116     1097      -19     

Impacted Files	Coverage Δ
pkg/network/payload/headers.go	100.00% <100.00%> (ø)
pkg/consensus/consensus.go	69.96% <0.00%> (-0.61%)	⬇️
pkg/vm/vm.go	93.96% <0.00%> (+0.57%)	⬆️
pkg/vm/stackitem/item.go	90.84% <0.00%> (+0.72%)	⬆️
pkg/core/interop/context.go	95.71% <0.00%> (+2.85%)	⬆️
pkg/vm/interop.go	83.58% <0.00%> (+2.98%)	⬆️
pkg/vm/context.go	90.72% <0.00%> (+3.09%)	⬆️
pkg/compiler/compiler.go	58.71% <0.00%> (+3.66%)	⬆️
pkg/compiler/analysis.go	96.72% <0.00%> (+9.01%)	⬆️
pkg/compiler/types.go	76.19% <0.00%> (+11.90%)	⬆️
... and 6 more

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