DAC - attempt retries and disable probe when ManagedIdentityCredential is selected in Env

[christothes]

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[Copilot]

Pull Request Overview

This PR implements a feature to disable probe requests and enable retries when ManagedIdentityCredential is explicitly configured via environment variables. The changes modify the DefaultAzureCredential behavior to skip the initial probe phase and allow exponential backoff retries when the credential chain is specifically configured to use ManagedIdentityCredential.

Key changes:

• Modified factory methods to accept a probe control parameter
• Added environment variable detection to disable probing when ManagedIdentityCredential is selected
• Added comprehensive test coverage for the new behavior

Reviewed Changes

Copilot reviewed 5 out of 5 changed files in this pull request and generated 2 comments.

Show a summary per file

File	Description
DefaultAzureCredentialFactory.cs	Modified CreateManagedIdentityCredential to accept probe control parameter and disable probing when called from environment variable configuration
TestDefaultAzureCredentialFactory.cs	Updated method signature to match base class changes
MockDefaultAzureCredentialFactory.cs	Updated method signature to match base class changes
ImdsManagedIdentityProbeSourceTests.cs	Added comprehensive test cases to verify probing is disabled and retries are enabled when ManagedIdentityCredential is configured via environment variables
CHANGELOG.md	Documented the new feature in the changelog