Remove session cookie only if they exist

We no longer send them on registration.
Signed-off-by: Michal Čihař <michal@cihar.com>

weblate/accounts/tests/test_registration.py

@@ -49,7 +49,7 @@ class RegistrationTest(TestCase, RegistrationTestMixin):
     def assert_registration(self, match=None):
         url = self.assert_registration_mailbox(match)
 
-        if self.clear_cookie:
+        if self.clear_cookie and 'sessionid' in self.client.cookies:
             del self.client.cookies['sessionid']
 
         # Confirm account
@@ -174,9 +174,6 @@ class RegistrationTest(TestCase, RegistrationTestMixin):
         # Remove session ID from URL
         url = url.split('&id=')[0]
 
-        # Delete session ID from cookies
-        del self.client.cookies['sessionid']
-
         # Confirm account
         response = self.client.get(url, follow=True)
         self.assertRedirects(response, reverse('login'))