Landscape：Shadowmap the landscape casting doesn't match visual mesh after build lighting

• Create a simpliest landscape with Resolution of 15 by 15(7*7 quads and 1*1 section, 2*2 Component)
• Put a big Staticmesh wall in level and Sculpt Landscape a bit for casting visible shadow on staticmeshes
• In Landscape editor, Manage mode, Select all Components of the Landscape, Set ForcedLOD=1
• Build lighting; Shadowmap the landscape casting doesn't match visual mesh after build lighting

Expect: The shadow should match the shape of landscape's LOD1

A test map attached; Put the folder upzipped into Content folder and open Shadowissuemap

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