Add a 'url' argument to .hydroportail_api
Suggested by @david.dorchies:
- to better see the dependencies with global variables of the package
- to be able to easily test for error codes using a URL reviewing a known code (https://httpstat.us/) or to be able to launch a request to a server that doesn't exist (to test for lack of internet connection) or a wrong request path on the hydroportal server