feature(currency): allow enums to be passed as currency

[CodeLieutenant]

It's really a common case to define currencies as enum, espacially with PHP 8.1, laravel also supports them (both saving and retrieving from the database).

Usecase

// Enums/Currency.php
enum Currency: string {
   case USD = 'USD';
}

// Models/Item.php
class Item extends Model {
   protected function casts(): array {
       return [
           'total' => MoneyDecimalCast::class . ':currency',
           'currency' => Currency::class,
       ];
   }
}

Without this, Money::parseCurrency just returns the enum passed to it and then Money\Money fails with exception, since it require $currency to be either string or Money\Currency

[codecov]

Codecov Report

❌ Patch coverage is 75.00000% with 1 line in your changes missing coverage. Please review.
✅ Project coverage is 99.79%. Comparing base (fdca65e) to head (20bcac9).
⚠️ Report is 2 commits behind head on main.

Files with missing lines	Patch %	Lines
src/CurrenciesTrait.php	75.00%	1 Missing ⚠️

Additional details and impacted files

@@              Coverage Diff              @@
##                main     #177      +/-   ##
=============================================
- Coverage     100.00%   99.79%   -0.21%     
- Complexity       172      174       +2     
=============================================
  Files             22       22              
  Lines            475      479       +4     
=============================================
+ Hits             475      478       +3     
- Misses             0        1       +1     

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[ricardogobbosouza]

Hi @CodeLieutenant

Just one thing the coverage complained about.

Thanks for the PR

[ricardogobbosouza]

This line is not being covered by the tests