[KGA-87] fix: high offset memory expansion computations

[enitrat]

Fixes computation on high memory offsets.
The remediation proposed by the audit finding was not sufficient enough. This one looks fine, although a bit more costly (even though uint256_add is not that computationally intensive)

https://github.com/code-423n4/2024-09-kakarot-findings/issues/4

---

This change is 

[notion-workspace]

Incorrect calculation in Gas::max_memory_expansion_cost for high offset zero size argument

[codecov]

Codecov Report

Attention: Patch coverage is 77.27273% with 5 lines in your changes missing coverage. Please review.

Project coverage is 63.6%. Comparing base (474951c) to head (d6eb900).
Report is 5 commits behind head on main.

Files with missing lines	Patch %	Lines
cairo_zero/kakarot/gas.cairo	77.2%	5 Missing ⚠️

Additional details and impacted files

@@           Coverage Diff           @@
##            main   #1604     +/-   ##
=======================================
- Coverage   63.6%   63.6%   -0.1%     
=======================================
  Files         44      44             
  Lines       8332    8343     +11     
=======================================
+ Hits        5301    5307      +6     
- Misses      3031    3036      +5     

☔ View full report in Codecov by Sentry.
📢 Have feedback on the report? Share it here.

[ClementWalter]

use from starkware.cairo.lang.cairo_constants import DEFAULT_PRIME