docs: Add Google Analytics configuration to conf.py (#2301)

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Fixes #<issue_number_goes_here> 🦕

Co-authored-by: Shuowei Li <[email protected]>

Author: tswast

docs/conf.py

@@ -172,6 +172,9 @@
             "url": "https://docs.cloud.google.com/bigquery/docs/bigquery-dataframes-introduction",
         },
     ],
+    "analytics": {
+        "google_analytics_id": "G-XVSRMCJ37X",
+    },
 }
 
 # Add any paths that contain custom themes here, relative to this directory.