fix fts index collection set
fix fts index collection set

Change-Id: If7fdc394f486759010a9adbe7454bde3aa891adc
Reviewed-on: https://review.couchbase.org/c/perfrunner/+/171761
Tested-by: Build Bot <80754af91bfb6d1073585b046fe0a474ce868509@couchbase.com>
Reviewed-by: Jyotsna <3cacb23db2a7c1408e4b8802d74c875d7724fa89@couchbase.com>

couchbase/perfrunner,couchbase/perfrunner,couchbase/perfrunner,couchbase/perfrunner,couchbase/perfrunner,couchbase/perfrunner