[FIX] web,website,tests: fix typo in test tags

This typo prevented two tests to run.

addons/web/tests/test_serving_base.py

@@ -14,7 +14,7 @@ def sample(population):
             random.randint(0, min(len(population), 5)))
 
 
-@tagged('stantard', 'at_install')
+@tagged('standard', 'at_install')
 class TestModulesLoading(unittest.TestCase):
     def setUp(self):
         self.mods = [str(i) for i in range(1000)]

addons/website/tests/test_converter.py

@@ -6,7 +6,7 @@ from odoo.addons.http_routing.models.ir_http import slugify, unslug
 from odoo.tests.common import tagged
 
 
-@tagged('stantard', 'at_install')
+@tagged('standard', 'at_install')
 class TestUnslug(unittest.TestCase):
 
     def test_unslug(self):

odoo/addons/base/tests/test_tests_tags.py

@@ -273,7 +273,7 @@ class TestSelectorSelection(TransactionCase):
         tags = TagsSelector('-slow,-standard')
         self.assertFalse(tags.check(multiple_tags_standard_obj))
 
-        tags = TagsSelector('stantard,-slow')
+        tags = TagsSelector('standard,-slow')
         self.assertFalse(tags.check(multiple_tags_standard_obj))
 
         tags = TagsSelector('slow,-standard')