chore: use ManagedIdentityCredential Instead of DefaultAzureCredential

[Priyanka-Microsoft]

Purpose

• ...
  This pull request introduces a centralized helper utility for managing Azure credentials and updates various components across the application to use this new utility. Additionally, it includes dependency updates and project configuration adjustments to support these changes.

Centralized Azure Credential Management:

• Added a new helper utility AzureCredentialHelper in App/backend-api/Microsoft.GS.DPS.Host/Helpers/azure_credential_utils.cs for managing Azure credentials based on the environment. This utility supports both DefaultAzureCredential (for development) and ManagedIdentityCredential (for production).
• Updated AppConfiguration.cs to use AzureCredentialHelper.GetAzureCredential() instead of directly instantiating DefaultAzureCredential.
• Updated multiple components across the kernel-memory directory to replace DefaultAzureCredential with azure_credential_utils.GetAzureCredential() for consistent credential management:
  • AzureAIDocIntelEngine.cs
  • AzureAISearchMemory.cs
  • AzureBlobsStorage.cs
  • AzureOpenAITextEmbeddingGenerator.cs
  • AzureOpenAITextGenerator.cs
  • AzureQueuesPipeline.cs
  • Service/Program.cs

Dependency Updates:

• Upgraded the Azure.Core package version from 1.42.0 to 1.47.1 in Directory.Packages.props to ensure compatibility with the new credential utility.

Project Configuration Adjustments:

• Added a new Helpers project (Helpers.csproj) to house the azure_credential_utils utility, targeting .NET 8.0 and including required Azure SDK dependencies.
• Updated various project files to reference the new Helpers project:
  • AzureAIDocIntel.csproj
  • AzureAISearch.csproj
  • AzureBlobs.csproj
  • AzureOpenAI.csproj
  • AzureQueues.csproj

Does this introduce a breaking change?

• Yes
• No

Golden Path Validation

• I have tested the primary workflows (the "golden path") to ensure they function correctly without errors.

Deployment Validation

• I have validated the deployment process successfully and all services are running as expected with this change.

What to Check

Verify that the following are valid

• ...

Other Information