Add `BUSY_WHILE_HEATING` for hosts that need it

Marlin/Configuration.h

Marlin/Marlin_main.cpp

Marlin/example_configurations/Anet/A6/Configuration.h

Marlin/example_configurations/CL-260/Configuration.h

Marlin/example_configurations/Cartesio/Configuration.h

Marlin/example_configurations/Felix/Configuration.h

Marlin/example_configurations/Felix/DUAL/Configuration.h

...example_configurations/FolgerTech-i3-2020/Configuration.h

Marlin/example_configurations/Hephestos/Configuration.h

Marlin/example_configurations/Hephestos_2/Configuration.h

...n/example_configurations/Infitary-i3-M508/Configuration.h

Marlin/example_configurations/K8200/Configuration.h

Marlin/example_configurations/K8400/Configuration.h

...in/example_configurations/K8400/Dual-head/Configuration.h

Marlin/example_configurations/M150/Configuration.h

...le_configurations/RepRapWorld/Megatronics/Configuration.h

Marlin/example_configurations/RigidBot/Configuration.h

Marlin/example_configurations/SCARA/Configuration.h

Marlin/example_configurations/TAZ4/Configuration.h

Marlin/example_configurations/TinyBoy2/Configuration.h