Decrease preliminary alert timeout to 1 min

Fixes #168.
10 jobs for preliminary-alert-timeout-one-minute in 7 minutes and 56 seconds (queued for 3 seconds)
Status Job ID Name Coverage
  Dist
passed #359900
dependencies/python3.6

00:00:47

passed #359901
dependencies/python3.7

00:00:37

passed #359899
sdist

00:01:02

 
  Test
passed #359902
bdist

00:00:38

passed #359906
doc

00:01:45

passed #359905
lint

00:00:53

passed #359903
test/python3.6

00:05:21

86.0%
passed #359904
test/python3.7

00:05:13

86.0%
 
  Deploy
passed #359907
docker/python3.6

00:01:02

passed #359908
docker/python3.7

00:00:56