Changes to Add product to watchlist

the productListingId response's property format changed from uuid to no format for status 201

the userId response's property format changed from uuid to no format for status 201

removed the required property source/sourceType from the response with the 400 status

removed the required property source/sourceType from the response with the 401 status

removed the required property source/sourceType from the response with the 403 status

removed the required property source/sourceType from the response with the 404 status

removed the required property source/sourceType from the response with the 409 status

removed the required property source/sourceType from the response with the 422 status

removed the required property source/sourceType from the response with the 500 status

the productListingId request property format was generalized from uuid to no format

added the required property source/type to the response with the 400 status

added the required property source/type to the response with the 401 status

added the required property source/type to the response with the 403 status

added the required property source/type to the response with the 404 status

added the required property source/type to the response with the 409 status

added the required property source/type to the response with the 422 status

added the required property source/type to the response with the 500 status

added the non-success response with the status 409