Add a way to send data to the server when requesting the cookie data

I found some issues with the first provided approach:

• - only one provider could be set, as the last one overrides the previous ones.
• - there could be some issues in case of different js loading times, when the provider js file was loaded before the library.

with the attached patch I changed the way we provide/collect the cacheable cookie handling providers, by treating more in a similar way Drupal core use the behaviours:

• - They are now stored in "their own" Drupal property cacheableCookieHandlingProviders so there's no risk that cacheableCookieHandling in not initialised if the JS are loaded in different order.
• - When cacheableCookieHandling init we search/loop that property and if we found some providers we use the provided data
• - Before this change the last provider set in the cacheableCookieHandling object was the only one that could provide data since it overrides the old ones (we don't have a case of multiple providers yet, but this could happens), now all the providers are manteined.

I also provided an updated example with this new logic implemented.