[Bug]: Copy project with circular milestone dependencies fails

[marcelfolaron]

What is your set up?

Cloud Hosted

Version

3.x

Describe the issue

From Discord. When a project is copied where milestones reference each other it may fail based on which milestone came first.
Adjust code to copy all items first and do the assignments afterwards.

Reproduction steps

1. Loop dependencies
2. Try copying project

Error Logs (LEANTIMEFOLDER/storage/logs)

Happening in project service 1097. Quick fix to check if milestone is set. (but that will remove the relationship if not set)