fix test

Author: dcherian

xarray/tests/test_combine.py

@@ -756,7 +756,7 @@ def test_auto_combine(self):
             auto_combine(objs)
 
         objs = [Dataset({"x": [0], "y": [0]}), Dataset({"x": [0]})]
-        with raises_regex(ValueError, "'y' is not present in all datasets"):
+        with raises_regex(KeyError, "'y'"):
             auto_combine(objs)
 
     def test_auto_combine_previously_failed(self):