update docfx.json - add default products metdata

adds a default products taxonomy URI in the globalMetdata section in addition to more granular definitions at fileMetadata level
Adds docs products taxonomy to the repo to improve findability experiences (onsite search, recommendations and others)
Added 
|Product Label| Taxonomy URI |
|---------|-----------|
| Azure|"https://authoring-docs-microsoft.poolparty.biz/devrel/68ec7f3a-2bc6-459f-b959-19beb729907d"|

docfx.json

@@ -211,6 +211,7 @@
       "ms.author": "routlaw",
       "author": "rloutlaw",
       "searchScope": [ "Azure", "Azure Java" ],
+      "products": ["https://authoring-docs-microsoft.poolparty.biz/devrel/68ec7f3a-2bc6-459f-b959-19beb729907d"],
       "_gitContribute": {
         "repo": "https://github.com/azure/azure-docs-sdk-java",
         "branch": "master",