Add delayed_project_deletion setting to Groups API

Problem to solve

In 13.2 a group-level setting was introduced to enable delayed deletion of projects. This is considered a critical setting by many organizations. However, currently it must be set manually because it is not supported in the Groups API. As a result, setting and confirming this setting can be extremely tedious.

Proposal

The Groups API:

• Returns delayed_project_removal in group details on 1) list and 2) show
• Accepts delayed_project_removal as an argument on 1) create and 2) update

The attributes should be allowed if adjourned_deletion_for_projects_and_groups feature is available in the License.

Related links

The pain of dealing with delayed_project_removal would be mitigated if sub-groups inherited the value of the setting, but would not be completely eliminated - so this issue seems to have value either way.