FIX: quick fix for yamlapi (this is deprecated)

src/caosdb/yamlapi.py

@@ -98,7 +98,7 @@ def yaml_to_xml(yamlstr):
         The string to load the yaml document from.
 
     """
-    return dict_to_xml(yaml.safe_load(yamlstr))
+    return dict_to_xml(yaml.load(yamlstr, Loader=yaml.SafeLoader))
 
 
 def process(text):