scripts: improve onebox script

[vagetablechicken]

OpenMLDB/onebox/start_onebox.sh

Lines 35 to 36 in 1aecdbc

	test -d tablet0-binlogs && rm -rf tablet0-binlogs
	test -d recycle_bin0 && rm -rf recycle_bin0

The onebox start script will create all dirs and logs in the root dir. It's hard to cleanup.
Plz move it to another place, and each server should have an unique log path(use -openmldb_log_dir=xxx).