Use wait_for_log instead of sleep in rpz test

This approach is a little bit more deterministic and hopefully
will make the rpz intermittent test failures go away.
39 jobs for !1660 with 921-rpz-manual-update-test-intermittent-fail in 13 minutes and 42 seconds (queued for 5 seconds)
detached
Status Job ID Name Coverage
  Precheck
passed #194528
amd64 linux
🐞:sid:amd64

00:00:37

passed #194527
amd64 linux
misc:sid:amd64

00:00:16

 
  Build
passed #194539
amd64 linux
asan:sid:amd64

00:05:11

passed #194540
amd64 linux
clang:stretch:amd64

00:02:31

passed #194541
i386 linux
clang:stretch:i386

00:01:29

passed #194529
amd64 linux
docs:sid:amd64

00:00:49

passed #194538
amd64 linux
gcc:bionic:amd64

00:01:29

passed #194530
amd64 linux
gcc:centos6:amd64

00:02:05

passed #194531
amd64 linux
gcc:centos7:amd64

00:01:54

passed #194536
amd64 linux
gcc:fedora29:amd64

00:02:03

passed #194532
amd64 linux
gcc:jessie:amd64

00:01:02

passed #194534
amd64 linux
gcc:sid:amd64

00:01:31

passed #194535
i386 linux
gcc:sid:i386

00:01:36

passed #194533
amd64 linux
gcc:stretch:amd64

00:01:34

passed #194537
amd64 linux
gcc:xenial:amd64

00:02:17

passed #194542
amd64 linux
pkcs11:sid:amd64

00:01:06

 
  Test
passed #194561
amd64 linux
system:asan:sid:amd64

00:07:54

passed #194559
amd64 linux
system:gcc:bionic:amd64

00:06:58

passed #194543
amd64 linux
system:gcc:centos6:amd64

00:06:14

passed #194545
amd64 linux
system:gcc:centos7:amd64

00:06:57

passed #194555
amd64 linux
system:gcc:fedora29:amd64

00:07:06

passed #194547
amd64 linux
system:gcc:jessie:amd64

00:06:47

passed #194551
amd64 linux
system:gcc:sid:amd64

00:06:58

passed #194553
i386 linux
system:gcc:sid:i386

00:06:52

passed #194549
amd64 linux
system:gcc:stretch:amd64

00:06:28

passed #194557
amd64 linux
system:gcc:xenial:amd64

00:06:29

passed #194564
amd64 linux
system:pkcs11:sid:amd64

00:06:59

passed #194562
amd64 linux
unit:asan:sid:amd64

00:01:00

passed #194563
amd64 linux
unit:clang:stretch:amd64

00:00:49

passed #194560
amd64 linux
unit:gcc:bionic:amd64

00:00:46

passed #194544
amd64 linux
unit:gcc:centos6:amd64

00:00:50

passed #194546
amd64 linux
unit:gcc:centos7:amd64

00:00:54

passed #194556
amd64 linux
unit:gcc:fedora29:amd64

00:00:52

passed #194548
amd64 linux
unit:gcc:jessie:amd64

00:00:38

passed #194552
amd64 linux
unit:gcc:sid:amd64

00:00:49

passed #194554
i386 linux
unit:gcc:sid:i386

00:00:52

passed #194550
amd64 linux
unit:gcc:stretch:amd64

00:00:50

passed #194558
amd64 linux
unit:gcc:xenial:amd64

00:00:54

passed #194565
amd64 linux
unit:pkcs11:sid:amd64

00:00:49