fix(EOF): Remove redundunt ext call gas cost

[rakita]

cold cost was deducted twice.

[github-actions]

Valgrind Results:

==3791== Cachegrind, a cache and branch-prediction profiler
==3791== Copyright (C) 2002-2017, and GNU GPL'd, by Nicholas Nethercote et al.
==3791== Using Valgrind-3.18.1 and LibVEX; rerun with -h for copyright info
==3791== Command: target/release/snailtracer
==3791== 
--3791-- warning: L3 cache found, using its data for the LL simulation.
Running snailtracer example!
elapsed: 1.811113202s
==3791== 
==3791== I   refs:      430,648,633
==3791== I1  misses:          3,176
==3791== LLi misses:          2,807
==3791== I1  miss rate:        0.00%
==3791== LLi miss rate:        0.00%
==3791== 
==3791== D   refs:      202,359,343  (131,535,012 rd   + 70,824,331 wr)
==3791== D1  misses:        339,192  (    198,938 rd   +    140,254 wr)
==3791== LLd misses:        137,818  (      4,329 rd   +    133,489 wr)
==3791== D1  miss rate:         0.2% (        0.2%     +        0.2%  )
==3791== LLd miss rate:         0.1% (        0.0%     +        0.2%  )
==3791== 
==3791== LL refs:           342,368  (    202,114 rd   +    140,254 wr)
==3791== LL misses:         140,625  (      7,136 rd   +    133,489 wr)
==3791== LL miss rate:          0.0% (        0.0%     +        0.2%  )