[tox] Allowing running of specific tests (#9097)

tests/sql_validator_tests.py

@@ -14,12 +14,14 @@
 # KIND, either express or implied.  See the License for the
 # specific language governing permissions and limitations
 # under the License.
+# isort:skip_file
 """Unit tests for Sql Lab"""
 import unittest
 from unittest.mock import MagicMock, patch
 
 from pyhive.exc import DatabaseError
 
+import tests.test_app
 from superset import app
 from superset.sql_validators import SQLValidationAnnotation
 from superset.sql_validators.base import BaseSQLValidator