Allow route to be a function

[piotrkochan]

I think that route should be allowed to be a function, because then GET endpoints like:

/api/customer/12345
/api/customer/67890

could be tested much better with random data.

[bvanderlaan]

You can define it as a function as long as you use the get descriptor.

{
  get route() {
    return `/api/customer/${customerId}`;
  },
}

The get descriptor makes the function a getter and can be invoked implicitly as if it was a property (i.e. options.route would invoke the above getter).