Improve data handling within process instance scope to allow to extract data for data input and outputs

Improve data handling within process instance scope to allow to extract data for data input and outputs to allow partial update of complex types being used as process variables - similar to what serverless workflow spec uses json path

Update variables partially. Example, update name attribute from a Customer object variable. This works in data input using mvel but not on output.

There are 2 related PRs in Kogito to migrate to jbpm:

• https://github.com/kiegroup/kogito-runtimes/pull/320
• https://github.com/kiegroup/kogito-runtimes/pull/314

Also, I migrated one test to ensure that it is not implemented in jBPM, you can use it as base for further migration.

• https://github.com/kiegroup/jbpm/pull/1617