Refactored felt252 dict libfuncs to use the BlockExt trait

[tcoratger]

Checklist

• Linked to Github Issue
• Unit tests added
• Integration tests added.
• This change requires new documentation.
  • Documentation has been added/updated.

[codecov-commenter]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 91.87%. Comparing base (b2f1568) to head (13dae88).
Report is 8 commits behind head on main.

Additional details and impacted files

@@            Coverage Diff             @@
##             main     #656      +/-   ##
==========================================
- Coverage   91.95%   91.87%   -0.09%     
==========================================
  Files         112      113       +1     
  Lines       34265    34577     +312     
==========================================
+ Hits        31509    31768     +259     
- Misses       2756     2809      +53     

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