Avoid dangerous file parsing and object serialization libraries.
yaml.load is the obvious function to use but it is dangerous[1]
Because yaml.load return Python object may be dangerous if you
receive a YAML document from an untrusted source such as the
Internet. The function yaml.safe_load limits this ability to
simple Python objects like integers or lists.
In addition, Bandit flags yaml.load() as security risk so replace
all occurrences with yaml.safe_load(). Thus I replace yaml.load()
with yaml.safe_load()
[1]https://security.openstack.org/guidelines/dg_avoid-dangerous-input-parsing-libraries.html
Change-Id: Ife71148013d5f94ec5ae62633ff9a41f419bd3b7
Closes-Bug: #1634265
cf81bd39a6