turn on reference issue indexing and switch to java index

tools/github-event-processor/Azure.Sdk.Tools.AI.Helper/README.md

@@ -45,7 +45,7 @@ dotnet run --command index --language java --mode reference-issues
 dotnet run --command index --language java --mode docs --path c:\repo\azure-sdk-for-java\sdk
 ```
 
-> Note: when indexing data, existing index with provided name is deleted first. If you want to preserve the index, pass `--delete_index false`
+> Note: when indexing data, existing index with provided name is deleted first. If you want to preserve the index, pass `--keep-index`
 
 You can always get cli help with `dotnet run -- -h`
 

tools/github-event-processor/Azure.Sdk.Tools.AI.Helper/appsettings.json

@@ -15,6 +15,6 @@
   },
   "Search": {
     "Endpoint": "https://lim-knowledge-base-search.search.windows.net",
-    "IndexName": "dotnet-issues-vector"
+    "IndexName": "java-vector"
   }
 }