Read Task after Update Task from a ReviewRequired SPI gives stale data

[CRoberto1926]

Steps to reproduce the problem:

• Implement the SPI ReviewRequiredProvider in the module taskana-rest-spring-example-boot
• Put a break point in the reviewRequired method to stop the execution
• Start 2 instances of taskana-rest-spring-example-boot using PostgreSQL
• Open the GUI, select a task to complete it: the break point should kick in
• While the execution of one instance is paused, call the update task endpoint on the other instance (e.g. PUT http://localhost:8081/taskana/api/v1/tasks/:taskId) and change a custom field
• Using another break point, check the output of getTask() in TaskServiceImpl.requestReview: the changes in the custom field from the update in the previous point should not be there