Test

Remove dead ractor_check_mode field #366

Job	Run time
check (Immix, debug, 150, macos-latest)	42m 14s
check (MarkSweep, release, ubuntu-latest)	11m 53s
check (Immix, debug, 150, ubuntu-latest)	1h 12m 36s
check (MarkSweep, debug, 150, macos-latest)	45m 9s
check (MarkSweep, debug, 150, ubuntu-latest)	1h 21m 7s
check (Immix, release, ubuntu-latest)	11m 34s
check (Immix, release, macos-latest)	4m 25s
check (MarkSweep, release, macos-latest)	12m 18s
	4h 41m 16s

Provide feedback