it can easily be done by editing the plugin login-google.php file
find the get_oauth_code function and update the params array
add hd parameter to array and mention your domain name.
$params = array(
‘response_type’ => ‘code’,
‘client_id’ => CLIENT_ID,
‘scope’ => SCOPE,
‘hd’ => ‘example.com’,
‘state’ => uniqid(”, true),
‘redirect_uri’ => REDIRECT_URI,
);
