Upgrade EVMC to v12.0.0

[chfast]

No description provided.

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 94.29%. Comparing base (9696fcf) to head (eca2f58).

Additional details and impacted files

@@           Coverage Diff           @@
##           master     #966   +/-   ##
=======================================
  Coverage   94.29%   94.29%           
=======================================
  Files         143      143           
  Lines       16129    16129           
=======================================
  Hits        15209    15209           
  Misses        920      920           

Flag	Coverage Δ
eof_execution_spec_tests	16.86% <ø> (ø)
ethereum_tests	26.92% <ø> (ø)
ethereum_tests_silkpre	18.69% <ø> (ø)
execution_spec_tests	17.95% <ø> (ø)
unittests	89.72% <ø> (ø)

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