docs: [google-shopping-merchant-conversions] change in wording : website -> online store (#12719)

- [ ] Regenerate this pull request now.

docs: A comment for message `MerchantCenterDestination` is changed
PiperOrigin-RevId: 635709955

Source-Link:
googleapis/googleapis@0ed8e06

Source-Link:
googleapis/googleapis-gen@d1754bc
Copy-Tag:
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---------

Co-authored-by: Owl Bot <gcf-owl-bot[bot]@users.noreply.github.com>

Author: gcf-owl-bot[bot]

packages/google-shopping-merchant-conversions/google/shopping/merchant_conversions_v1beta/types/conversionsources.py

@@ -278,8 +278,9 @@ class GoogleAnalyticsLink(proto.Message):
 
 class MerchantCenterDestination(proto.Message):
     r""" "Merchant Center Destination" sources can be used to send
-    conversion events from a website using a Google tag directly to
-    a Merchant Center account where the source is created.
+    conversion events from an online store using a Google tag
+    directly to a Merchant Center account where the source is
+    created.
 
     Attributes:
         destination (str):