Add disable instance discovery to DAC (Azure#34257)

Author: billwert

sdk/identity/azure-identity/CHANGELOG.md

@@ -8,6 +8,7 @@
 
 ### Bugs Fixed
 - Fixed detection logic for az/azd.
+- Add `disableInstanceDiscovery` to `DefaultAzureCredentialBuilder`
 
 ## 1.8.1 (2023-03-06)
 

sdk/identity/azure-identity/src/main/java/com/azure/identity/DefaultAzureCredentialBuilder.java

@@ -218,6 +218,17 @@ public DefaultAzureCredentialBuilder additionallyAllowedTenants(List<String> add
         return this;
     }
 
+    /**
+     * Disable instance discovery. Instance discovery is acquiring metadata about an authority from https://login.microsoft.com
+     * to validate that authority. This may need to be disabled in private cloud or ADFS scenarios.
+     *
+     * @return An updated instance of this builder with instance discovery disabled.
+     */
+    public DefaultAzureCredentialBuilder disableInstanceDiscovery() {
+        this.identityClientOptions.disableInstanceDisovery();
+        return this;
+    }
+
     /**
      * Creates new {@link DefaultAzureCredential} with the configured options set.
      *