Common parts extracted + more changes for #984

[n9]

Common parts from ReadablePropertiesTypeInspector and WritablePropertiesTypeInspector are extracted to PropertiesTypeInspector and more changes to support #984:

• virtual method PropertiesTypeInspector.CreateProperty
• public property ReflectionPropertyDescriptor.PropertyInfo

[n9]

PS: During the refactoring I found that the type inspectors might need more refactoring:

The ReadableAndWritablePropertiesTypeInspector only checks if properties are writable, but despite its name it does not check if they are readable.

YamlDotNet/YamlDotNet/Serialization/TypeInspectors/ReadableAndWritablePropertiesTypeInspector.cs

Lines 44 to 48 in 7923dd8

	public override IEnumerable<IPropertyDescriptor> GetProperties(Type type, object? container)
	{
	return innerTypeDescriptor.GetProperties(type, container)
	.Where(p => p.CanWrite);
	}

Maybe it should be renamed to something like WritablePropertiesTypeInspectorFilter? (But that would be a breaking change.)

Do you want to create an issue for this?