Add system event when entity is deleted

• Type: Technical Task
• Status: Closed
• Priority: Minor
• Resolution: Completed
• Affects Version/s: 6.2.0 CE M6
• Fix Version/s: 6.2.0 CE M6
• Component/s: Staging, Staging > Export/Import
• Labels: None
• Git Pull Request: https://github.com/brianchandotcom/liferay-portal/pull/11662

In order to be able to export deletions to the LAR file, we need to create records of deletions in the system. The way we're doing this is creating entries in the SystemEventEntry table.