nodepool elements: use yaml.safe_load
The recent pyyaml 6 release, incorporated in the latest
nodepool-builder/dib images, requires a specific loader now.  Use
safe_load as there's nothing crazy going on here.
@@ -42,7 +42,7 @@ CUSTOM_PROJECTS_LIST_URL = os.environ.get('DIB_CUSTOM_PROJECTS_LIST_URL')
def get_project_list(url):
try:
projects = []
- for f in yaml.load(urlopen(url)):
+ for f in yaml.safe_load(urlopen(url)):
# Skip repos that are inactive
project = f['project']
dirname = os.path.dirname(project)
