Using "Change Class" on Spawnables, Possessable references retain old Class info

Changing Class for Spawnable objects in Level Sequence did not have any impact on Possesable objects in Subsequence. It's still referencing the previous Class.

Also found in Release-5.4, CL: 32975355

1. Download the licensee’s test project and open (see addl. info URL 2)
2. Open Level Sequence "/Game/Sequencer/ClassChange/ClassChange"
3. Hover over Spawnable BP Third Person Character. It will shows that Class is set to "BP_ThirdPersonCharacter_Alternate"
4. Inside Sequence open Subsequence named shot0010_01 and click on Possessable character
5. Run "SequencerDebug" Editor Utility Widget located at: "/Game/Blueprints/SequencerDebug"
6. Observe that the Class reported shows the Subsequence referencing "BP_ThirdPersonCharacter"
7. In the main sequence "ClassChange", right click the Spawnable BP Third Person Character, and change its class to some other class (such as the "ArchVisCharacter")
8. In the subsequence shot0010_01, use the SequenceDebug Editor Utility Widget to show that the class remains "BP_ThirdPersonCharacter"