Add LEVEL_CORNERS_HEIGHT to LEVEL_BED_CORNERS (#13439)

Marlin/Configuration.h

Marlin/src/lcd/menu/menu_bed_corners.cpp

config/default/Configuration.h

config/examples/3DFabXYZ/Migbot/Configuration.h

config/examples/AlephObjects/TAZ4/Configuration.h

config/examples/AliExpress/CL-260/Configuration.h

config/examples/AliExpress/UM2pExt/Configuration.h

config/examples/Anet/A2/Configuration.h

config/examples/Anet/A2plus/Configuration.h

config/examples/Anet/A6/Configuration.h

config/examples/Anet/A8/Configuration.h

config/examples/AnyCubic/i3/Configuration.h

config/examples/ArmEd/Configuration.h

config/examples/Azteeg/X5GT/Configuration.h

config/examples/BIBO/TouchX/cyclops/Configuration.h

config/examples/BIBO/TouchX/default/Configuration.h

config/examples/BQ/Hephestos/Configuration.h

config/examples/BQ/Hephestos_2/Configuration.h

config/examples/BQ/WITBOX/Configuration.h

config/examples/Cartesio/Configuration.h