rbac updates

Author: Blackmist

articles/ai-studio/concepts/rbac-ai-studio.md

@@ -262,6 +262,8 @@ When using Microsoft Entra ID authenticated connections in the chat playground,
 | Search Service Contributor | Azure AI services / Azure OpenAI | Azure AI Search | Read-write access to object definitions (indexes, aliases, synonym maps, indexers, data sources, and skillsets). Inference service queries the index schema for auto fields mapping. Data ingestion service creates index, data sources, skill set, indexer, and queries the indexer status. |
 | Cognitive Services OpenAI Contributor | Azure AI Search | Azure AI services / Azure OpenAI | Custom skill |
 | Cognitive Services OpenAI User | Azure OpenAI Resource for chat model | Azure OpenAI resource for embedding model | Required only if using two Azure OpenAI resources to communicate. |
+| Storage Blob Data Contributor | Azure AI Search | Azure Storage Account | Reads blob and writes knowledge store. |
+| Storage Blob Data Contributor | Azure AI services / Azure OpenAI | Azure Storage Account | Reads from the input container and writes the preprocess results to the output container. |
 
 > [!NOTE]
 > The __Cognitive Services OpenAI User__ role is only required if you are using two Azure OpenAI resources: one for your chat model and one for your embedding model. If this applies, enable Trusted Services AND ensure the connection for your embedding model Azure OpenAI resource has Microsoft Entra ID enabled.