Prevent a race in the "inline" system test

A short time window exists between logging the addition of an NSEC3PARAM
record to a zone and committing it to the current version of the zone
database.  If a query arrives during such a time window, an unsigned
response will be returned.  One of the checks in the "inline" system
test requires NSEC3 records to be present in an answer - that check
would fail in the case described above.  Use rndc instead of log
watching for checking whether zone signing and NSEC3 chain modifications
are complete in order to prevent intermittent "inline" system test
failures.

(cherry picked from commit e36c869e)
14 jobs for 491-prevent-a-race-in-the-inline-system-test-v9_11 in 8 minutes and 7 seconds (queued for 5 seconds)
Status Job ID Name Coverage
  Precheck
passed precheck:debian:sid:amd64 #44828
amd64 docker linux

00:00:16

 
  Build
passed build:centos:centos6:amd64 #44829
amd64 docker linux

00:02:49

passed build:centos:centos7:amd64 #44830
amd64 docker linux

00:02:58

passed build:debian:sid:amd64 #44831
amd64 docker linux

00:02:40

passed build:debian:sid:i386 #44832
i386 docker linux

00:02:50

 
  Test
passed install:debian:sid:amd64 #44841
amd64 docker linux

00:02:10

passed systemtest:centos:centos6:amd64 #44837
amd64 docker linux

00:04:31

passed systemtest:centos:centos7:amd64 #44838
amd64 docker linux

00:04:40

passed systemtest:debian:sid:amd64 #44839
amd64 docker linux

00:04:39

passed systemtest:debian:sid:i386 #44840
i386 docker linux

00:04:51

passed unittest:centos:centos6:amd64 #44833
amd64 docker linux

00:01:13

passed unittest:centos:centos7:amd64 #44834
amd64 docker linux

00:01:15

passed unittest:debian:sid:amd64 #44835
amd64 docker linux

00:01:04

passed unittest:debian:sid:i386 #44836
i386 docker linux

00:00:50