ExpoPushMessage does not support categoryId

[steson322]

The node package contains categoryId but the Java version does not. This critically blocks certain features.

https://github.com/expo/expo-server-sdk-node

[jav]

Sorry about my inactivity.
@oliverwelter has offered to be a new maintainer.
The new repository lies here: https://github.com/nia-medtech/expo-server-sdk-java