[all hosts] Update product metadata (#718)

Author: ElizabethSamuel-MSFT

docs/docfx.json

@@ -48,6 +48,7 @@
       "ms.topic": "conceptual",
       "ms.subservice": "scripts",
       "ms.service": "excel",
+      "product": ["office", "office-excel"],
       "open_source_feedback_contributorGuideUrl": "https://github.com/OfficeDev/office-scripts-docs/blob/main/Contributing.md",
       "open_source_feedback_issueTitle": "",
       "open_source_feedback_issueUrl": "https://github.com/OfficeDev/office-scripts-docs/issues/new?template=3_customer-feedback.yml",