Make a subtask removes task from its current project and list

[jdorleans]

Whenever making a subtask from a task already added to a project, its project is removed.

Steps to reproduce:

1. Create a task
2. Add it to a project
3. Move it to a list - e.g. In Progress
4. Make it a subtask of another task
5. Project of this task is removed - FAIL
6. List task was in is also removed - FAIL

Expected:
Project and list task was in should not be removed.

Browser version:
Chrome: 80.0.3987.87 (64-bit)
Firefox: 72.0.2 (64-bit)