sanity-test should fail fast when properties are missing

[bodymindarts]

When properties for the fog-check script in sanity-test aren't set sanity-test runs but fails:

+ fog-check
+ cat /var/vcap/jobs/sanity-test/config/fog-clusterdata.yml

+ cat /var/vcap/jobs/sanity-test/config/fog-databasestorage.yml

+ cd /var/vcap/packages/dingo-postgresql-fog-check
+ bundle exec bin/dingo-postgresql-fog-check /var/vcap/jobs/sanity-test/config/fog-clusterdata.yml /var/vcap/jobs/sanity-test/config/fog-databasestorage.yml

File /var/vcap/jobs/sanity-test/config/fog-clusterdata.yml could not be found or YAML parsed

The reason is because the fog-clusterdata.yml conditionally adds the properties:

<% if_p("backups.clusterdata.aws_access_key_id", "backups.clusterdata.aws_secret_access_key", "backups.clusterdata.bucket_name") do |aws_access_key_id, aws_secret_access_key, bucket_name| %>
...

Either the properties are mandatory and we don't use if_p making sanity-test fail when trying to provision (due to missing properties) or if the properties are really optional then sanity test shouldn't fail when those properties are not present.

[drnic]

Yep that's not nice.