chore(qa): update db upgrade pom version
fix(engine): clear cached variable value on varaible deletion

related to CAM-3167
test(cdi): bean resolution during deployment

- e.g. for timer start events

test case for CAM-3163
test(engine): test cmmn task/stage manual activation rule

- adds failing test cases for plan item activation rules
- adds working test cases for plan item definition default activation rules

related to CAM-3169 CAM-3170
fix(engine): deserialize value in first command

if a serialized value is set, it can be deserialized in the same command
if so requested.

related to #CAM-3174