Merge ~chad.smith/cloud-init:bug/1769754-salt-minion-bionic into cloud-init:master

[Chad Smith]

tests: fix salt_minion integration test on bionic and later

In ubuntu, the salt-minion package version 2017.7.4+dfsg1-1 or later
automatically moves any seed keys from /etc/salt/pki/minion/ to
/var/lib/salt/pki/minion/. Fix integration tests to collect
either files in either /etc/salt/pki/minion/ or
/var/lib/salt/pki/minion/.

for series in artful bionic cosmic; do
  tox -e citest -- run --os-name $series --test modules/salt_minion --verbose;
done

[Server Team CI bot (server-team-bot)]

PASSED: Continuous integration, rev:6523126b97d5532cf127bb479800cdb43e62c003
https://jenkins.ubuntu.com/server/job/cloud-init-ci/78/
Executed test runs:
    SUCCESS: Checkout
    SUCCESS: Unit & Style Tests
    SUCCESS: Ubuntu LTS: Build
    SUCCESS: Ubuntu LTS: Integration
    SUCCESS: MAAS Compatability Testing
    IN_PROGRESS: Declarative: Post Actions

Click here to trigger a rebuild:
https://jenkins.ubuntu.com/server/job/cloud-init-ci/78/rebuild

review: Approve (continuous-integration)

[Joshua Powers (powersj)]

review: Approve

[Chad Smith (chad.smith)]

An upstream commit landed for this bug.

To view that commit see the following URL:
https://git.launchpad.net/cloud-init/commit/?id=27283c31

diff --git a/tests/cloud_tests/testcases/modules/salt_minion.yaml b/tests/cloud_tests/testcases/modules/salt_minion.yaml
index c24aa17..9227147 100644
--- a/tests/cloud_tests/testcases/modules/salt_minion.yaml
+++ b/tests/cloud_tests/testcases/modules/salt_minion.yaml
@@ -28,10 +28,20 @@ collect_scripts:
     cat /etc/salt/minion_id
   minion.pem: |
     #!/bin/bash
-    cat /etc/salt/pki/minion/minion.pem
+    PRIV_KEYFILE=/etc/salt/pki/minion/minion.pem
+    if [ ! -f $PRIV_KEYFILE ]; then
+        # Bionic and later automatically moves /etc/salt/pki/minion/*
+        PRIV_KEYFILE=/var/lib/salt/pki/minion/minion.pem
+    fi
+    cat $PRIV_KEYFILE
   minion.pub: |
     #!/bin/bash
-    cat /etc/salt/pki/minion/minion.pub
+    PUB_KEYFILE=/etc/salt/pki/minion/minion.pub
+    if [ ! -f $PUB_KEYFILE ]; then
+        # Bionic and later automatically moves /etc/salt/pki/minion/*
+        PUB_KEYFILE=/var/lib/salt/pki/minion/minion.pub
+    fi
+    cat $PUB_KEYFILE
   grains: |
     #!/bin/bash
     cat /etc/salt/grains