Fix outdated code examples

[JulianGCalderon]

This PR fixes some outdated code examples.

The following examples are still failing, because support for them has yet not been implemented:

• examples/factorial.con
• examples/union.con

What should we do with these files? Should we move them to another directory examples/unimplemented?

Also, the example examples/check_error.con fails, but given its name maybe its on purpose. Should be move it another directory examples/failing?

[codecov-commenter]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 56.29%. Comparing base (4802a28) to head (d43ab59).

Additional details and impacted files

@@           Coverage Diff           @@
##             main     #230   +/-   ##
=======================================
  Coverage   56.29%   56.29%           
=======================================
  Files          25       25           
  Lines        5516     5516           
=======================================
  Hits         3105     3105           
  Misses       2411     2411           

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[github-actions]

Benchmarking (macOS) factorial

Compiling factorial (factorial.con)
Finished release in 577.572084ms
Running 5000000 iterations
Using input value: 20
Concrete Result = 2432902008176640000 Time taken : 31.14 ms
Rust Result = 2432902008176640000 Time taken : 25.25 ms

Benchmarking (macOS) fib

Compiling fib (fib.con)
Finished release in 112.836959ms
Running 5000 iterations
Using input value: 20
Concrete Result = 6765 Time taken : 92.83 ms
Rust Result = 6765 Time taken : 102.22 ms

[github-actions]

Benchmarking (Linux) factorial

Compiling factorial (factorial.con)
Finished release in 32.498991ms
Running 5000000 iterations
Using input value: 20
Concrete Result = 2432902008176640000 Time taken : 96.97 ms
Rust Result = 2432902008176640000 Time taken : 60.42 ms

Benchmarking (Linux) fib

Compiling fib (fib.con)
Finished release in 26.124224ms
Running 5000 iterations
Using input value: 20
Concrete Result = 6765 Time taken : 137.09 ms
Rust Result = 6765 Time taken : 85.70 ms