Exclude logging sinks

Those sinks are too coarse grained to be exposed as sinks on any model.

java/ql/test/utils/model-generator/p/Sinks.java

@@ -7,6 +7,7 @@ import java.nio.file.CopyOption;
 import java.nio.charset.Charset;
 import java.nio.file.Files;
 import java.nio.file.Path;
+import java.util.logging.Logger;
 
 public class Sinks {
     
@@ -25,4 +26,9 @@ public class Sinks {
         String foo = new Sinks().readUrl(new URL(args[0]), Charset.defaultCharset());
     }
 
+    public void propagate(String s) {
+        Logger logger = Logger.getLogger(Sinks.class.getSimpleName());
+        logger.warning(s);
+    }
+
 }