remove decorator that is not compatible with all CDS datasets (#605)

* remove decorator that is not compatible with all CDS datasets

Author: EddyCMWF

src/earthkit/data/sources/cds.py

@@ -145,7 +145,6 @@ def retrieve(target, args):
         return return_object
 
     @staticmethod
-    @normalize("date", "date-list(%Y-%m-%d)")
     @normalize("area", "bounding-box(list)")
     def _normalize_request(**kwargs):
         return kwargs

tests/sources/test_cds.py

@@ -128,6 +128,14 @@ def test_cds_grib_split_on_var():
             "2012-12-12/to/2012-12-14",
             [20121212, 20121212, 20121213, 20121213, 20121214, 20121214],
         ),
+        (
+            "2012-12-12/2012-12-14",
+            [20121212, 20121212, 20121213, 20121213, 20121214, 20121214],
+        ),
+        (
+            ["2012-12-12/2012-12-14"],
+            [20121212, 20121212, 20121213, 20121213, 20121214, 20121214],
+        ),
         (
             ["2014-05-12", "2014-05-13", "2014-05-14"],
             [20140512, 20140512, 20140513, 20140513, 20140514, 20140514],