Introduce a global DecoratorOrder enum/constant holder to avoid enhancers cross referencing each other

[hatzlj]

Enhancement Description

Decorators in Axon Framework are registered using an absolute order values. It is a common pattern currently to store the decorators intended order in a constant on the decorator's class level and to make the value of the order relative to another decorator by cross referencing the constant of another decorator's constant. To avoid this cross referencing we should introduce a global DecoratorOrder enum/interface holding constants that can be referenced.

Current Behaviour

Decorators are cross-referencing each other to ensure relative ordering.

Wanted Behaviour

Decorators are only cross-referencing via a global decorator order enum/interface

Possible Workarounds

• keep cross referencing
• allow different means of relative ordering like Allow for ComponentDecorator registration ordering through a Predicate #3316