Converts an object type T into a type with the same keys, but with all values wrapped in a function that returns that value.
type User = {
id: number;
name: string;
age: number;
email: string;
date: Date;
};
type UserGetters = Getters<User>;
// output
type UserGetters = {
id: () => number;
name: () => string;
age: () => number;
email: () => string;
date: () => Date;
};