Update call to yaml.load() due to deprecation warning (#271)

See: https://github.com/yaml/pyyaml/wiki/PyYAML-yaml.load(input)-Deprecation

nordicsemi/zigbee/prod_config.py

@@ -62,7 +62,7 @@ def __init__(self, path):
         try:
             # Open the YAML file
             with open(path, 'r') as f:
-                self._yaml = yaml.load(f)
+                self._yaml = yaml.load(f, Loader=yaml.FullLoader)
 
         except yaml.YAMLError as e:
             raise ProductionConfigWrongException