Add a new function to generate random datetime within a range around a base date. This allows the base date to change in the future or to be set to today's date easily.
closes odoo/odoo#48636 X-original-commit: f3f2a1e4723240b6396cea943fc86291c16f4c9d Signed-off-by: Xavier Dollé (xdo) <xdo@odoo.com>