Add support of anonymous functions

[xzxzxc]

The following code

MiniValidator.TryValidate(new TestOptions(), out _);

public class TestOptions
{
  public Func<object?> SomeFunc { get; set; } = () => null;
}

Throws

System.InvalidOperationException
Method may only be called on a Type for which Type.IsGenericParameter is true.
   at System.RuntimeType.get_DeclaringMethod()
   at MiniValidation.PropertyHelper.CallNullSafePropertyGetter[TDeclaringType,TValue](Func`2 getter, Object target) in /_/src/MiniValidation/PropertyHelper.cs:line 129
   at MiniValidation.PropertyDetails.GetValue(Object target) in /_/src/MiniValidation/TypeDetailsCache.cs:line 256
   at MiniValidation.MiniValidator.TryValidateImpl(Object target, IServiceProvider serviceProvider, Boolean recurse, Boolean allowAsync, Dictionary`2 workingErrors, Dictionary`2 validatedObjects, List`1 validationResults, String prefix, Int32 currentDepth) in /_/src/MiniValidation/MiniValidator.cs:line 402
   at MiniValidation.MiniValidator.TryValidateImpl(Object target, IServiceProvider serviceProvider, Boolean recurse, Boolean allowAsync, Dictionary`2 workingErrors, Dictionary`2 validatedObjects, List`1 validationResults, String prefix, Int32 currentDepth) in /_/src/MiniValidation/MiniValidator.cs:line 499
   at MiniValidation.MiniValidator.TryValidateImpl(Object target, IServiceProvider serviceProvider, Boolean recurse, Boolean allowAsync, Dictionary`2 workingErrors, Dictionary`2 validatedObjects, List`1 validationResults, String prefix, Int32 currentDepth) in /_/src/MiniValidation/MiniValidator.cs:line 499
   at MiniValidation.MiniValidator.TryValidateImpl(Object target, IServiceProvider serviceProvider, Boolean recurse, Boolean allowAsync, Dictionary`2 workingErrors, Dictionary`2 validatedObjects, List`1 validationResults, String prefix, Int32 currentDepth) in /_/src/MiniValidation/MiniValidator.cs:line 499
   at MiniValidation.MiniValidator.TryValidateImpl[TTarget](TTarget target, IServiceProvider serviceProvider, Boolean recurse, Boolean allowAsync, IDictionary`2& errors) in /_/src/MiniValidation/MiniValidator.cs:line 188
   at MiniValidation.MiniValidator.TryValidate[TTarget](TTarget target, IDictionary`2& errors) in /_/src/MiniValidation/MiniValidator.cs:line 59

The issue is that the compiler generates a type representing the anonymous function that breaks validation.

There is a workaround, adding the SkipRecursion attribute, but in my case, the type I want to validate is declared in a separate library, which I have no access to, so I have to skip validation of the whole type. So it would be great if MiniValidation would support this out of the box.