feat: add Firebolt DB engine spec (#16903)

* New branch from superset for integration with firebolt sqlalchemy adapter

* Added db_engine_spec file for Firebolt

* Removed firebolt code from superset repo

* Deleted virtual env commit

* Adding time grain changes to firebolt.py

* Updated README.md

Added steps to install and run Superset with Firebolt SQLAlchemy Adapter

* Update README.md

Reduced installation steps. Using PyPi installation for adapter now

* Revert "Update README.md"

This reverts commit 5ed17c7a45.

* Revert "Updated README.md"

This reverts commit 45c5072649.

* added epoch methods, added test cases for firebolt db engine spec and edited setup.py

* Added license to files

* Added documentation for Firebolt-SQLAlchemy

* Removed trailing whitespace

Co-authored-by: raghavsharma <raghavs@sigmoidanalytics.com>
Co-authored-by: raghavSharmaSigmoid <88667094+raghavSharmaSigmoid@users.noreply.github.com>

tests/integration_tests/db_engine_specs/firebolt_tests.py

@@ -0,0 +1,39 @@
+# 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.firebolt import FireboltEngineSpec
+from tests.integration_tests.db_engine_specs.base_tests import TestDbEngineSpec
+
+
+class TestFireboltDbEngineSpec(TestDbEngineSpec):
+    def test_convert_dttm(self):
+        dttm = self.get_dttm()
+        test_cases = {
+            "DATE": "CAST('2019-01-02' AS DATE)",
+            "DATETIME": "CAST('2019-01-02T03:04:05' AS DATETIME)",
+            "TIMESTAMP": "CAST('2019-01-02T03:04:05' AS TIMESTAMP)",
+            "UNKNOWNTYPE": None,
+        }
+
+        for target_type, expected in test_cases.items():
+            actual = FireboltEngineSpec.convert_dttm(target_type, dttm)
+            self.assertEqual(actual, expected)
+
+    def test_epoch_to_dttm(self):
+        assert (
+            FireboltEngineSpec.epoch_to_dttm().format(col="timestamp_column")
+            == "from_unixtime(timestamp_column)"
+        )