Implicit Gson library dependency should be removed

[solatarius]

Is your feature request related to a problem? Please describe.

The EventData class which is defined in the Event object has a member object of type JsonObject which is a type defined by the com.google.gson library.

When I try to deserialize stored json into an Event object using a com.fasterxml.jackson ObjectMapper, errors are thrown because the object jsonString contains fields not explicitly defined by the JsonObject.

https://github.com/stripe/stripe-java/blob/master/src/main/java/com/stripe/model/EventData.java#L28

Describe the solution you'd like

The object field of the EventData class should be of type Map<String, Object> or something similar... and anywhere else in the models where JsonObject is used, it should be replaced with the same solution

Describe alternatives you've considered

No response

Additional context

No response

[dcr-stripe]

Hi @solatarius , thanks for the report!

We generally would like to support Jackson more generally. I've split out #1344 to track this as a top-level feature request.

[pizzi80]

maybe it's better to move to standard Java Json Binding (JSR 367)

https://javaee.github.io/jsonb-spec/