add tests

Author: jiasli

src/azure-cli-core/azure/cli/core/_profile.py

@@ -437,7 +437,8 @@ def get_login_credentials(self, subscription_id=None, aux_subscriptions=None, au
                 str(account[_SUBSCRIPTION_ID]),
                 str(account[_TENANT_ID]))
 
-    def get_raw_token(self, resource=None, scopes=None, subscription=None, tenant=None):
+    def get_raw_token(self, resource=None, scopes=None, subscription=None, tenant=None, credential_out=None):
+        # credential_out is only used for unit tests to inspect the credential. Do not use it!
         # Convert resource to scopes
         if resource and not scopes:
             from .auth.util import resource_to_scopes
@@ -467,6 +468,8 @@ def get_raw_token(self, resource=None, scopes=None, subscription=None, tenant=No
                 raise CLIError("Tenant shouldn't be specified for managed identity account")
             if _use_msal_managed_identity(self.cli_ctx):
                 cred = MsiAccountTypes.msal_credential_factory(managed_identity_type, managed_identity_id)
+                if credential_out:
+                    credential_out['credential'] = cred
                 sdk_cred = CredentialAdaptor(cred)
             else:
                 from .auth.util import scopes_to_resource