cephtool/test.sh: Only delete a test pool when no longer needed.

cephtool/test.sh: Only delete a test pool when no longer needed.

the pool_getset pool is deleted before all tests on it are complete

4: /home/jenkins/workspace/ceph-master/qa/workunits/cephtool/test.sh:1990: test_mon_osd_pool_set:  ceph osd pool delete pool_get
set pool_getset --yes-i-really-really-mean-it
4: pool 'pool_getset' removed
4: /home/jenkins/workspace/ceph-master/qa/workunits/cephtool/test.sh:1992: test_mon_osd_pool_set:  ceph osd pool get rbd crush_r
ule
4: /home/jenkins/workspace/ceph-master/qa/workunits/cephtool/test.sh:1992: test_mon_osd_pool_set:  grep 'crush_rule: '
4: crush_rule: replicated_rule
4: /home/jenkins/workspace/ceph-master/qa/workunits/cephtool/test.sh:1994: test_mon_osd_pool_set:  ceph -f json osd pool get poo
l_getset compression_mode
4: Error ENOENT: unrecognized pool 'pool_getset'

Signed-off-by: Willem Jan Withagen <wjw@digiware.nl>