Fix instruction tracing of EOF code

[gumb0]

After #531 tracer gets state.original_code and then uses PC value to get an opcode from this code, which is incorrect for EOF.

I don't have a fix yet, but wrote a test.

[codecov]

Codecov Report

Merging #536 (ec2ea9f) into master (83ad7bc) will increase coverage by 0.03%.
The diff coverage is 100.00%.

Additional details and impacted files

@@            Coverage Diff             @@
##           master     #536      +/-   ##
==========================================
+ Coverage   97.99%   98.03%   +0.03%     
==========================================
  Files          59       59              
  Lines        5681     5687       +6     
==========================================
+ Hits         5567     5575       +8     
+ Misses        114      112       -2     

Flag	Coverage Δ
blockchaintests	78.15% <44.44%> (-0.24%)	⬇️
statetests	72.76% <44.44%> (-0.15%)	⬇️
unittests	91.71% <100.00%> (+<0.01%)	⬆️

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Impacted Files	Coverage Δ
lib/evmone/baseline.cpp	100.00% <100.00%> (ø)
lib/evmone/baseline.hpp	100.00% <100.00%> (ø)
lib/evmone/instructions.hpp	100.00% <100.00%> (+0.21%)	⬆️
test/unittests/tracing_test.cpp	100.00% <100.00%> (ø)
lib/evmone/advanced_analysis.hpp	100.00% <0.00%> (+2.94%)	⬆️