ライトマップのアセットをすべて削除し、ベイク前の状態に戻します
Only those assets are deleted that are in the folder with the same name as the scene name
AND their name follows the pattern LightmapFar-#.exr or LightmapNear-#.exr.
If LightmapEditorSettings.lockAtlas is disabled, it will also clear the lightmaps array and
clear lightmap indices on all objects.
ベイクされたライトプローブもクリアされます。