🎉 New Source: Firebase Realtime Database (#18029)

* implement check for source-firebase-realtime-database

* implement discover

* support only one stream

* implement read and tests

* add docs

* remove unnecessary file

* add pr number

* fix sat

* add bootstrap.md

* add badge in builds.md

* fix acceptance.py

* add supported_sync_modes in configured_catalog

* add database_name description and example

* add info about required role for service account

* remove abnormal_state.json

* fill catalog.json with values for testing

* loosen requirements

* Update Dockerfile

* auto-bump connector version

* readd firebase to seed file

* fix build gradle for firebase

---------

Co-authored-by: Tuan Nguyen <anhtuan.nguyen@me.com>
Co-authored-by: Marcos Marx <marcosmarxm@users.noreply.github.com>
Co-authored-by: Octavia Squidington III <octavia-squidington-iii@users.noreply.github.com>
Co-authored-by: marcosmarxm <marcosmarxm@gmail.com>

airbyte-integrations/connectors/source-firebase-realtime-database/unit_tests/unit_test.py

@@ -0,0 +1,73 @@
+#
+# Copyright (c) 2022 Airbyte, Inc., all rights reserved.
+#
+
+import string
+
+import pytest
+from source_firebase_realtime_database.firebase_rtdb import Records
+from source_firebase_realtime_database.source import SourceFirebaseRealtimeDatabase
+
+
+@pytest.mark.parametrize(
+    "config, stream_name",
+    [
+        (
+            {"database_name": "my-database", "path": "users"},
+            "users",
+        ),
+        (
+            {"database_name": "my-database", "path": "/users"},
+            "users",
+        ),
+        (
+            {"database_name": "my-database", "path": "path/to/product-details"},
+            "product_details",
+        ),
+        (
+            {"database_name": "my-database", "path": "path/to/product-details/"},
+            "product_details",
+        ),
+        (
+            {"database_name": "my-database", "path": ""},
+            "my_database",
+        ),
+    ],
+)
+def test_stream_name_from(config, stream_name):
+
+    actual = SourceFirebaseRealtimeDatabase.stream_name_from(config)
+    expected = stream_name
+
+    assert actual == expected
+
+
+class PseudoClient:
+    """
+    Pseudo client producing records which keys and values are ordered ASCII chcaracter
+    ex. {"a": "a", "b": "b", "c": "c"}
+    """
+
+    def __init__(self, buffer_size):
+        self._buffer_size = buffer_size
+
+    def fetch_records(self, start_key=None):
+        if start_key:
+            start = ord(start_key) - ord("a")
+        else:
+            start = 0
+
+        end = start + self._buffer_size
+
+        return {c: c for c in string.ascii_lowercase[start:end]}
+
+
+def test_records():
+    buffer_size = 5
+    client = PseudoClient(buffer_size)
+    records = Records(client)
+
+    expected = [{"key": c, "value": f'"{c}"'} for c in string.ascii_lowercase]
+    actual = list(records)
+
+    assert actual == expected