Inserted facts via BusinessRuleTaskHandler don't match rules because of different classloaders

Custom "BusinessRuleTask" is executed by org.jbpm.process.workitem.bpmn2.BusinessRuleTaskHandler

https://docs.jbpm.org/latest/jbpm-docs/html_single/#con_custom-tasks-overview

(Note that this is different from a standard "Business rule task" https://docs.jbpm.org/latest/jbpm-docs/html_single/#bpmn-tasks-overview-con_business-processes)

Assuming you specify BusinessRuleTaskHandler (language=DRL) to execute the same GAV kjar as the process project, BusinessRuleTaskHandler allows to insert a fact via Data Input. However, if the fact class exists in the process project kjar, the inserted fact class is associated with process project's classloader, while ObjectTypeNode.objectType in the rule kbase (created by BusinessRuleTaskHandler) is associated with a different classloader. So the fact doesn't match the rule.

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• Add a DRL test to BusinessRuleTaskTest (jbpm-test-coverage)
• Add a DecisionTasksIntegrationTest (kie-server-integ-tests-all) variant. Use BusinessRuleTaskHandler instead of RemoteBusinessRuleTaskHandler.