feat: Switch from nosetest to pytest (#10177)

* Switch from nosetest to pytest

Fix schedule tests

Collect pytest coverage

Move pytest config into pytest.ini

Move cov to the pytest.ini

* Append coverage for the 2nd run

* Add coverage to all commands

* Coverage only for tests

* Get coverage from 1 place

* Rename classes to be  pytest compatible

* Test coverage for examples and tests

* Max diff to -1

* Explain how to run pytest for the whole project

* Do not append code coverage for the main run

* Do not run coverage on examples

Co-authored-by: bogdan kyryliuk <bogdankyryliuk@dropbox.com>

tests/sqllab_tests.py

@@ -40,12 +40,9 @@ QUERY_2 = "SELECT * FROM NO_TABLE"
 QUERY_3 = "SELECT * FROM birth_names LIMIT 10"
 
 
-class SqlLabTests(SupersetTestCase):
+class TestSqlLab(SupersetTestCase):
     """Testings for Sql Lab"""
 
-    def __init__(self, *args, **kwargs):
-        super(SqlLabTests, self).__init__(*args, **kwargs)
-
     def run_some_queries(self):
         db.session.query(Query).delete()
         db.session.commit()