evm: unit tests

[fedekunze]

Closes: ENG-153

[codecov]

Codecov Report

Merging #619 (77e950f) into main (f69c887) will increase coverage by 4.52%.
The diff coverage is 16.66%.

@@            Coverage Diff             @@
##             main     #619      +/-   ##
==========================================
+ Coverage   51.49%   56.01%   +4.52%     
==========================================
  Files          63       63              
  Lines        5502     5502              
==========================================
+ Hits         2833     3082     +249     
+ Misses       2501     2257     -244     
+ Partials      168      163       -5     

Impacted Files	Coverage Δ
x/evm/types/dynamic_fee_tx.go	89.67% <ø> (+89.67%)	⬆️
x/evm/types/msg.go	70.94% <ø> (ø)
x/evm/types/params.go	100.00% <ø> (+32.35%)	⬆️
x/evm/types/tracer.go	46.42% <0.00%> (+46.42%)	⬆️
x/evm/types/legacy_tx.go	100.00% <100.00%> (+26.78%)	⬆️
x/evm/types/chain_config.go	100.00% <0.00%> (+2.54%)	⬆️
x/evm/types/tx_data.go	84.09% <0.00%> (+6.81%)	⬆️
x/evm/types/genesis.go	100.00% <0.00%> (+14.28%)	⬆️
... and 3 more