[CDC] KV using wrong time unit in time callbacks

Steps to repro:

1. Create a single cluster
2. Create a magma bucket with (history_retention_collection_default=true,bucket_history_retention_seconds=86400,bucket_history_retention_bytes=96636764160) (Vbucket count = 1)
3. Create one collection(total collections including default are two)
4. Create 1000 documents(doc size = 1024 bytes)
5. Update 1000 docs with expiry(set to 15 seconds)
6. Sleep for 15 seconds for docs to expire
7. Set expiry pagers time to 10 seconds
8. Wait until exp_pager_stime for kv_purger to kickoff
9. wait for 300 seconds for KV purger to scan expired docs and add tombstones
10. Until this point all the stats shows correct value

    vb_0:high_seqno: 3001

    vb_0:history_start_seqno: 1

11. ReSet expiry pagers time to 10000000000 seconds
12. Recreate 1000 docs with expiry set to 13 seconds
13. Sleep for 13 seconds for docs to expire
14. Set expiry pagers time to 10 seconds
15. # Wait until exp_pager_stime for kv_purger to kickoff
16. wait for 300 seconds for KV purger to scan expired docs and add tombstones
17. Stats now also shows correct value

    -bash-4.2# /opt/couchbase/bin/cbstats localhost:11210 -u Administrator -p password -b default vbucket-details 0 | grep -e history -e high_seqno

    vb_0:high_seqno: 5001

    vb_0:history_start_seqno: 1

18. Repeat steps 11 to 15(this time expiry is set to 12 seconds)
19. History start seq number gets set to new value 5002

    -bash-4.2# /opt/couchbase/bin/cbstats localhost:11210 -u Administrator -p password -b default vbucket-details 0 | grep -e history -e high_seqn

    vb_0:high_seqno: 6001

    vb_0:history_start_seqno: 5002

    -bash-4.2#

    -bash-4.2#

    -bash-4.2# /opt/couchbase/bin/cbstats localhost:11210 -u Administrator -p password -b default vbucket-details 0 | grep -e history -e high_seqn

    vb_0:high_seqno: 7001

    vb_0:history_start_seqno: 5002

QE-TEST:

git fetch https://review.couchbase.org/TAF refs/changes/62/186462/2 && git checkout -b change-186462 FETCH_HEAD

guides/gradlew --refresh-dependencies testrunner -P jython=/opt/jython/bin/jython -P 'args=-i /tmp/temp_vol_3.ini -p bucket_storage=magma,bucket_ram_quota=256,init_loading=False,bucket_eviction_policy=fullEviction,rerun=False -t storage.magma.cdc_steady_state.SteadyStateTests.test_history_retention_for_n_expire_iterations,nodes_init=1,skip_cleanup=True,num_items=1000,doc_size=1024,batch_size=1000,sdk_timeout=60,log_level=info,infra_log_level=info,key_size=22,num_collections=2,ops_rate=20000,key_type=RandomKey,vbuckets=1,replicas=2,test_itr=10,bucket_history_retention_seconds=86400,bucket_history_retention_bytes=96636764160,standard_buckets=1,magma_buckets=1,num_scopes=1 -m rest'