check that the time between notify messages is not too small

(cherry picked from commit 47a4e0ee)
21 jobs for 760-the-notify-system-test-incorrectly-detects-startup-notify-rate-error-v9_11 in 15 minutes and 9 seconds (queued for 10 seconds)
Status Job ID Name Coverage
  Precheck
passed precheck:debian:sid:amd64 #124273
amd64 docker linux

00:00:17

 
  Build
passed build:asan:debian:sid:amd64 #124277
amd64 docker linux

00:01:46

passed build:centos:centos6:amd64 #124274
amd64 docker linux

00:02:07

passed build:centos:centos7:amd64 #124275
amd64 docker linux

00:02:21

passed build:debian:sid:amd64 #124276
amd64 docker linux

00:01:42

passed build:debian:sid:i386 #124278
i386 docker linux

00:01:33

passed noassert:build:debian:sid:amd64 #124279
amd64 docker linux

00:01:27

 
  Test
passed docs:debian:sid:amd64 #124280
amd64 docker linux

00:00:44

passed install:debian:sid:amd64 #124291
amd64 docker linux

00:02:25

passed noassert:systemtest:debian:sid:amd64 #124293
amd64 docker linux

00:05:01

passed noassert:unittest:debian:sid:amd64 #124292
amd64 docker linux

00:00:49

passed systemtest:asan:debian:sid:amd64 #124289
amd64 docker linux

00:06:28

passed systemtest:centos:centos6:amd64 #124286
amd64 docker linux

00:04:56

passed systemtest:centos:centos7:amd64 #124287
amd64 docker linux

00:05:20

passed systemtest:debian:sid:amd64 #124288
amd64 docker linux

00:05:19

passed systemtest:debian:sid:i386 #124290
i386 docker linux

00:05:21

passed unittest:asan:debian:sid:amd64 #124284
amd64 docker linux

00:01:37

passed unittest:centos:centos6:amd64 #124281
amd64 docker linux

00:00:46

passed unittest:centos:centos7:amd64 #124282
amd64 docker linux

00:00:55

passed unittest:debian:sid:amd64 #124283
amd64 docker linux

00:00:46

passed unittest:debian:sid:i386 #124285
i386 docker linux

00:00:45