Restore Documentum Repository in order to release it

• Type: Task
• Status: Closed
• Priority: Minor
• Resolution: Completed
• Affects Version/s: None
• Fix Version/s: 7.1.X, 7.2.X, Master
• Component/s: External Document Repositories > Documentum
• Labels: None
• Branch Version/s:
  7.2.x, 7.1.x
• Backported to Branch:
  Committed
• Epic/Theme:
  • Technical_Task
• Git Pull Request: https://github.com/brianchandotcom/liferay-portal-ee/pull/21165

As the component is deprecated, its code was removed from the main repository. There's still one (final) release pending, so the code needs to be restored.