b2: fix inconsistent listings and rclone check
b2: fix inconsistent listings and rclone check

This was caused by re-using a variable for the results of a JSON
unmarshal and the unmarshaller picking up existing entries.

See https://forum.rclone.org/t/check-command-gives-unreliable-results/

olihey/rclone,ncw/rclone,seuffert/rclone,olihey/rclone,yonjah/rclone,B4dM4n/rclone,seuffert/rclone,seuffert/rclone,B4dM4n/rclone,olihey/rclone,ncw/rclone,ncw/rclone,B4dM4n/rclone,yonjah/rclone,yonjah/rclone,yonjah/rclone,seuffert/rclone,ncw/rclone,olihey/rclone,B4dM4n/rclone