[KGA-34] feat: update base fee starting from next block only

[enitrat]

https://github.com/code-423n4/2024-09-kakarot-findings/issues/28

Updates the base fee mechanism.

In the EVM there can only be one base fee for a given block.
Thus, we use an index to manage two different base fees:
- The base fee to use for the current block (index: 'current_block')
- The base fee to use for the next block (index: 'next_block')

The startegy is:

• when getting the base fee, check if you can get the one from the 'next_block' (if block_number > next_fee_start_block_number)
• if yes, then update the value in current_block and return the new value
• otherwise, return the value from current_block

When setting the base_fee, it will be applicable starting from block_number + 1.

Note: for tests we have to manually patch both addr and addr+1 as we'restoring two values.

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This change is 

[notion-workspace]

base fee updates implementation deviates from EIP-1559

[codecov]

Codecov Report

Attention: Patch coverage is 96.00000% with 1 line in your changes missing coverage. Please review.

Project coverage is 63.7%. Comparing base (289c2e8) to head (3fb7fed).
Report is 4 commits behind head on main.

Files with missing lines	Patch %	Lines
cairo_zero/kakarot/library.cairo	90.9%	1 Missing ⚠️

Additional details and impacted files

@@          Coverage Diff          @@
##            main   #1606   +/-   ##
=====================================
  Coverage   63.6%   63.7%           
=====================================
  Files         44      44           
  Lines       8343    8364   +21     
=====================================
+ Hits        5309    5328   +19     
- Misses      3034    3036    +2     

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