private static async Task <bool> RemoveGroupOwner(string grpName, string userName)
        {
            try
            {
                // get object id for userPrincipalName
                var userObjectId = GetUserObjectId(userName).GetAwaiter().GetResult();

                // get object id fro group name
                var groupObjectId = GetGroupObjectId(grpName).GetAwaiter().GetResult();

                AuthenticationConfig config = AuthenticationConfig.ReadFromJsonFile("appsettings.json");

                // call MS Graph Api function that attaches a member to the group
                var httpClient = new HttpClient();
                var apiCaller  = new ProtectedApiCallHelper(httpClient);
                await apiCaller.DeleteWebApiAndProcessResultASync($"{config.ApiUrl}v1.0/groups/{groupObjectId}/owners/{userObjectId}/$ref",
                                                                  Program.AuthenticationResult.AccessToken);

                return(true);
            }
            catch (Exception ex)
            {
                return(false);
            }
        }
        private static async Task DeleteGroup(string groupName)
        {
            AuthenticationConfig config = AuthenticationConfig.ReadFromJsonFile("appsettings.json");

            try
            {
                var groupId = MsGraphFacade.GetGroupObjectId(groupName).GetAwaiter().GetResult();

                var httpClient = new HttpClient();
                var apiCaller  = new ProtectedApiCallHelper(httpClient);
                await apiCaller.DeleteWebApiAndProcessResultASync($"{config.ApiUrl}v1.0/groups/{groupId}", Program.AuthenticationResult.AccessToken);
            }
            catch (Exception ex)
            {
                Debug.WriteLine(ex.Message);
            }
        }