Merge pull request #6 from kristeligt-dagblad/bug/kmeans-learning-rate

Set learning rate to null for kmeans in audit hook.

macros/hooks/model_audit.sql

@@ -43,7 +43,7 @@ kmeans:
         - iteration
         - loss
         - cast(null as float64) as eval_loss
-        - learning_rate
+        - cast(null as float64) as learning_rate
         - duration_ms
         - cluster_info
     feature_info: *default_feature_info