[design-patterns/mediator]Colleague&Mediator存在互相依赖关系

[GourdErwa]

Describe the bug
[design-patterns/mediator]Colleague&Mediator存在互相依赖关系.

To Reproduce
Steps to reproduce the behavior:

1. Go to 'inetllijIDEA'
2. Click on 'Analyze>Depend~ Matrix'
3. See DSM