fix: Use program builtins in initialize_main_entrypoint & read_return_values

[fmoletta]

Fixes these two methods, and other inconsistencies in other methods.
Add tests to run programs with missing builtins

[codecov]

Codecov Report

Attention: Patch coverage is 86.27451% with 14 lines in your changes are missing coverage. Please review.

Project coverage is 94.93%. Comparing base (ca3b8ab) to head (2c8cb4d).

Files	Patch %	Lines
vm/src/cairo_run.rs	16.66%	5 Missing ⚠️
vm/src/vm/runners/builtin_runner/modulo.rs	0.00%	5 Missing ⚠️
vm/src/vm/runners/builtin_runner/mod.rs	85.71%	2 Missing ⚠️
vm/src/vm/runners/cairo_runner.rs	97.10%	2 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #1703      +/-   ##
==========================================
- Coverage   94.96%   94.93%   -0.04%     
==========================================
  Files          99       99              
  Lines       38532    38579      +47     
==========================================
+ Hits        36592    36625      +33     
- Misses       1940     1954      +14     

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