Key input by Sequencer is missing in FBX output of parent-child actors

This problem did not occur in 4.27.0.

Animation is not output when outputting a hierarchical structure.

Actor(A)
　　┗Actor(B)
　　　　┗Actor(C)

This is how the attachments are registered, and the key is placed in the Transform Track of each ABC.

4.27.0
Animation is output for both ABCs

4.27.1
AB's Animation is not output, only C's Animation is output

1. Add two arbitrary actors as Spawnable to a new sequencer.
2. Add a Key to the TransformTrack of Actor (A).
3. Attach Actor (B) to Actor (A) using AttachTrack.
4. Select Actor (A), perform export operation on the sequencer (opiton is default), and output fbx(ascii).
5. Load the fbx in the DCC tool and make sure there is no animation.