schedule: do not report status for first and last in suite jobs

schedule: do not report status for first and last in suite jobs

Addresses the issue when teuthology run gets stuck with
first_in_suite or laste_in_suite jobs in queued state.

Attention: This change requires the next steps,
which are not mutually exclusive:

 1) server teuthology worker restart, otherwise old
    worker's code will try to remove reported job
    from paddles and exit with unexpected exception.
 2) user's teuthology runner environment should be
    updated to recent code, because new workers will
    not cleanup FIS and LIS jobs and they will remain
    in paddles, correspondingly the run will get stuck.

Requires: a34fb6a3694538db8496b3bc599c3e62b9acaca6

Fixes: http://tracker.ceph.com/issues/43291
Signed-off-by: Kyr Shatskyy <kyrylo.shatskyy@suse.com>