According to the tests, Project::putInTrash doesnt work
Please, fix the method Project::putInTrash :
java.util.ConcurrentModificationException
at java.base/java.util.ArrayList.forEach(ArrayList.java:1513)
at fr.alma.gtd.server.core.AbstractProject.putInTrash(AbstractProject.java:119)
at fr.alma.gtd.server.main.donnees.ProjectTest.testIsTrash(ProjectTest.java:172)