update py/unsafe-deserialization to match ruby/javascript/java

Author: erik-krogh

python/ql/src/Security/CWE-502/UnsafeDeserialization.ql

@@ -18,4 +18,4 @@ import DataFlow::PathGraph
 
 from Configuration config, DataFlow::PathNode source, DataFlow::PathNode sink
 where config.hasFlowPath(source, sink)
-select sink.getNode(), source, sink, "Deserializing of $@.", source.getNode(), "untrusted input"
+select sink.getNode(), source, sink, "Unsafe deserialization of $@.", source.getNode(), "user input"