fix(validation): Fix validation when input is empty and not required

fix(db): Prevent saving a useless empty database value when country is selected by number field is empty

plugin.php

@@ -4,7 +4,7 @@
  * Plugin Name: Advanced Custom Fields: Phone Number
  * Plugin URI:  https://github.com/log1x/acf-phone-number
  * Description: A real ACF phone number field.
- * Version:     1.0.2
+ * Version:     1.0.4
  * Author:      Brandon Nifong
  * Author URI:  https://github.com/log1x
  */