ci: Build clang/sanitizers with libc++

[chfast]

Closes https://github.com/ethereum/evmone/issues/906.

[codecov[bot]]

Codecov Report

All modified and coverable lines are covered by tests :white_check_mark:

Project coverage is 94.29%. Comparing base (0987d83) to head (0d295da). Report is 1 commits behind head on master.

Additional details and impacted files

@@           Coverage Diff           @@
##           master     #918   +/-   ##
=======================================
  Coverage   94.29%   94.29%           
=======================================
  Files         159      159           
  Lines       17323    17323           
=======================================
  Hits        16335    16335           
  Misses        988      988           

Flag	Coverage Δ
eof_execution_spec_tests	15.90% <ø> (ø)
ethereum_tests	26.88% <ø> (ø)
ethereum_tests_silkpre	18.97% <ø> (ø)
execution_spec_tests	21.10% <ø> (ø)
unittests	89.03% <ø> (ø)

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