[REM] mass_mailing: remove useless db param in url

Methods _get_unsubscribe_url and _get_tracking_url
create url with a db parameter (GET), but it isn't used
in the targeted controller. Then we removed it.

task-2087379

closes odoo/odoo#40568

Signed-off-by: Thibault Delavallee (tde) <tde@openerp.com>

addons/mass_mailing/models/mail_mail.py

@@ -29,12 +29,7 @@ class MailMail(models.Model):
 
     def _get_tracking_url(self):
         base_url = self.env['ir.config_parameter'].sudo().get_param('web.base.url')
-        track_url = werkzeug.urls.url_join(
-            base_url, 'mail/track/%(mail_id)s/blank.gif?%(params)s' % {
-                'mail_id': self.id,
-                'params': werkzeug.urls.url_encode({'db': self.env.cr.dbname})
-            }
-        )
+        track_url = werkzeug.urls.url_join(base_url, 'mail/track/%s/blank.gif' % self.id)
         return '<img src="%s" alt=""/>' % track_url
 
     def _get_unsubscribe_url(self, email_to):
@@ -43,7 +38,6 @@ class MailMail(models.Model):
             base_url, 'mail/mailing/%(mailing_id)s/unsubscribe?%(params)s' % {
                 'mailing_id': self.mailing_id.id,
                 'params': werkzeug.urls.url_encode({
-                    'db': self.env.cr.dbname,
                     'res_id': self.res_id,
                     'email': email_to,
                     'token': self.mailing_id._unsubscribe_token(