formatting null adoption (#44)

Author: max-ostapenko

definitions/output/reports/cwv_tech_adoption.js

@@ -20,8 +20,8 @@ SELECT
   rank,
   geo,
   STRUCT(
-    COALESCE(MAX(IF(client = 'desktop', origins, NULL))) AS desktop,
-    COALESCE(MAX(IF(client = 'mobile', origins, NULL))) AS mobile
+    COALESCE(MAX(IF(client = 'desktop', origins, 0))) AS desktop,
+    COALESCE(MAX(IF(client = 'mobile', origins, 0))) AS mobile
   ) AS adoption
 FROM ${ctx.ref('core_web_vitals', 'technologies')}
 WHERE date = '${pastMonth}'