Bug#1002462: bls service discontinued - remove from tracker.d.o?

Control: unblock 1002462 with 944620

The BLS service has been discontinued, back in January:
https://qa.debian.org/bls/

Its last report file was never removed, so tracker.d.o continues to
display that stale data.  It's probably time to remove the corresponding
action item from tracker pages entirely.