Don't fail when pulling previous build image fails (eg: image does not exist).

9 jobs for master in 10 minutes and 55 seconds
Status Job ID Name Coverage
  Test Build
failed #45668182
build

00:05:23

passed #45667135
codequality

00:07:06

passed #45667132
dataset_mysql

00:03:50

passed #45667133
dataset_postgres

00:03:48

passed #45667129
test

00:00:50

45.0%
passed #45667130
test_mysql

00:05:16

45.0%
passed #45667131
test_postgres

00:04:42

45.0%
failed #45667134
build

00:05:30

 
  Staging
skipped #45667136
staging
 
Name Stage Failure
failed
build Test Build There is an unknown failure, please try again
9231c775624c: Waiting
04e536435e19: Waiting
a4aa58eb9a50: Waiting
8ddb34736d66: Waiting
0533a8638027: Waiting
9fccad5277f0: Waiting
cfce7a8ae632: Waiting
denied: requested access to the resource is denied
ERROR: Job failed: exit code 1