refactor(tests): decouple unittests from integration tests (#15473)

* refactor move all tests to be under integration_tests package

* refactor decouple unittests from integration tests - commands

* add unit_tests package

* fix celery_tests.py

* fix wrong FIXTURES_DIR value

tests/integration_tests/db_engine_specs/athena_tests.py

@@ -0,0 +1,57 @@
+# Licensed to the Apache Software Foundation (ASF) under one
+# or more contributor license agreements.  See the NOTICE file
+# distributed with this work for additional information
+# regarding copyright ownership.  The ASF licenses this file
+# to you under the Apache License, Version 2.0 (the
+# "License"); you may not use this file except in compliance
+# with the License.  You may obtain a copy of the License at
+#
+#   http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing,
+# software distributed under the License is distributed on an
+# "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+# KIND, either express or implied.  See the License for the
+# specific language governing permissions and limitations
+# under the License.
+from superset.db_engine_specs.athena import AthenaEngineSpec
+from superset.errors import ErrorLevel, SupersetError, SupersetErrorType
+from tests.integration_tests.db_engine_specs.base_tests import TestDbEngineSpec
+
+
+class TestAthenaDbEngineSpec(TestDbEngineSpec):
+    def test_convert_dttm(self):
+        dttm = self.get_dttm()
+
+        self.assertEqual(
+            AthenaEngineSpec.convert_dttm("DATE", dttm),
+            "from_iso8601_date('2019-01-02')",
+        )
+
+        self.assertEqual(
+            AthenaEngineSpec.convert_dttm("TIMESTAMP", dttm),
+            "from_iso8601_timestamp('2019-01-02T03:04:05.678900')",
+        )
+
+    def test_extract_errors(self):
+        """
+        Test that custom error messages are extracted correctly.
+        """
+        msg = ": mismatched input 'fromm'. Expecting: "
+        result = AthenaEngineSpec.extract_errors(Exception(msg))
+        assert result == [
+            SupersetError(
+                message='Please check your query for syntax errors at or near "fromm". Then, try running your query again.',
+                error_type=SupersetErrorType.SYNTAX_ERROR,
+                level=ErrorLevel.ERROR,
+                extra={
+                    "engine_name": "Amazon Athena",
+                    "issue_codes": [
+                        {
+                            "code": 1030,
+                            "message": "Issue 1030 - The query has a syntax error.",
+                        }
+                    ],
+                },
+            )
+        ]