docs: [google-shopping-css] update Certification field descriptions (…

…#13027)

- [ ] Regenerate this pull request now.

PiperOrigin-RevId: 665432329

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googleapis/googleapis@5988300

Source-Link:
googleapis/googleapis-gen@bc2954f
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packages/google-shopping-css/google/shopping/css_v1/types/css_product_common.py

@@ -494,15 +494,27 @@ class Attributes(proto.Message):
 
 
 class Certification(proto.Message):
-    r"""The certification for the product.
+    r"""The certification for the product. Use the this attribute to
+    describe certifications, such as energy efficiency ratings,
+    associated with a product.
 
     Attributes:
         name (str):
-            Name of the certification.
+            The name of the certification. At this time,
+            the most common value is "EPREL", which
+            represents energy efficiency certifications in
+            the EU European Registry for Energy Labeling
+            (EPREL) database.
         authority (str):
-            Name of the certification body.
+            The authority or certification body responsible for issuing
+            the certification. At this time, the most common value is
+            "EC" or “European_Commission” for energy labels in the EU.
         code (str):
-            A unique code to identify the certification.
+            The code of the certification. For example,
+            for the EPREL certificate with the link
+            https://eprel.ec.europa.eu/screen/product/dishwashers2019/123456
+            the code is 123456. The code is required for
+            European Energy Labels.
     """
 
     name: str = proto.Field(