Fixed a bug that cannot configure heated bed temperature more than once
Fixed a bug that cannot configure heated bed temperature more than once

cheton/cnc,cncjs/cncjs,cheton/piduino-grbl,cheton/cnc.js,cheton/cnc,cncjs/cncjs,cheton/piduino-grbl,cheton/cnc,cheton/cnc.js,cheton/cnc.js,cncjs/cncjs,cheton/piduino-grbl