Suggestion: Mark all functions that represent deprecated paypal api resources as deprecated in godoc comment.

[thomasf]

A comment string`that looks something like this so they are clearly marked in godoc

// Deprecated: This API resource is deprecated by PayPal.

Just to make godoc clearer like this https://pkg.go.dev/github.com/plutov/paypal/v4#Resource

[sbshah97]

Hi is there something I can contribute to ?

[plutov]

@sbshah97 yes please review the code and add the annotations.