Since PyYAML 5.1, yaml.load without specifying the Loader option is
deprecated and shows the following warning.
YAMLLoadWarning: calling yaml.load() without Loader=... is deprecated,
as the default Loader is unsafe.
Please read https://msg.pyyaml.org/load for full details.
This change replaces yaml.load by yaml.safe_load (which is effectively
same as adding Loader=yaml.SafeLoader) to get rid of that warning
message. Also, existing all usage of yaml.load with the Loader option
are also replaced so that we to make all implementation to load yaml
files consistent.
Change-Id: Id44fa2354429b944fbc0809f63db558bb7de23f7
53040573ab