fix: dont calculate initcode keccak on CREATE

[rakita]

Calculating keccak on CREATE opcode is unnecessary as it is only needed on CREATE2. init_code_hash is needed only for foundry so setting B256::ZERO can work.

[github-actions]

Valgrind Results:

==3932== Cachegrind, a cache and branch-prediction profiler
==3932== Copyright (C) 2002-2017, and GNU GPL'd, by Nicholas Nethercote et al.
==3932== Using Valgrind-3.18.1 and LibVEX; rerun with -h for copyright info
==3932== Command: target/release/snailtracer
==3932== 
--3932-- warning: L3 cache found, using its data for the LL simulation.
==3932== 
==3932== I   refs:      456,276,177
==3932== I1  misses:          3,005
==3932== LLi misses:          2,636
==3932== I1  miss rate:        0.00%
==3932== LLi miss rate:        0.00%
==3932== 
==3932== D   refs:      229,453,815  (152,512,579 rd   + 76,941,236 wr)
==3932== D1  misses:        349,991  (    210,174 rd   +    139,817 wr)
==3932== LLd misses:        137,003  (      3,750 rd   +    133,253 wr)
==3932== D1  miss rate:         0.2% (        0.1%     +        0.2%  )
==3932== LLd miss rate:         0.1% (        0.0%     +        0.2%  )
==3932== 
==3932== LL refs:           352,996  (    213,179 rd   +    139,817 wr)
==3932== LL misses:         139,639  (      6,386 rd   +    133,253 wr)
==3932== LL miss rate:          0.0% (        0.0%     +        0.2%  )

[gakonst]

easy enough

[mattsse]

this looks reasonable