Use DefaultNetworkCredentials if the current credentials should be used

Commands/Base/SPOnlineConnectionHelper.cs

@@ -562,6 +562,12 @@ internal static SPOnlineConnection InstantiateSPOnlineConnection(Uri url, PSCred
                 {
                     context.Credentials = new NetworkCredential(credentials.UserName, credentials.Password);
                 }
+                else
+                {
+                    // If current credentials should be used, use the DefaultNetworkCredentials of the CredentialCache. This has the same effect
+                    // as using "UseDefaultCredentials" in a HttpClient.
+                    context.Credentials = CredentialCache.DefaultNetworkCredentials;
+                }
             }
 #if SP2013 || SP2016 || SP2019
             var connectionType = ConnectionType.OnPrem;