fix(document_loaders/telegram): fix pandas calls + add tests (#4806)

# Fix Telegram API loader + add tests.
I was testing this integration and it was broken with next error:
```python
message_threads = loader._get_message_threads(df)
KeyError: False
```
Also, this particular loader didn't have any tests / related group in
poetry, so I added those as well.

@hwchase17 / @eyurtsev please take a look on this fix PR.

---------

Co-authored-by: Dev 2049 <dev.dev2049@gmail.com>

tests/unit_tests/document_loaders/test_json_loader.py

@@ -0,0 +1,123 @@
+import pytest
+from pytest import raises
+from pytest_mock import MockerFixture
+
+from langchain.docstore.document import Document
+from langchain.document_loaders.json_loader import JSONLoader
+
+
+@pytest.mark.requires("jq")
+def test_load_valid_string_content(mocker: MockerFixture) -> None:
+    file_path = "/workspaces/langchain/test.json"
+    expected_docs = [
+        Document(
+            page_content="value1",
+            metadata={"source": file_path, "seq_num": 1},
+        ),
+        Document(
+            page_content="value2",
+            metadata={"source": file_path, "seq_num": 2},
+        ),
+    ]
+    mocker.patch("builtins.open", mocker.mock_open())
+    mock_csv_reader = mocker.patch("pathlib.Path.read_text")
+    mock_csv_reader.return_value = '[{"text": "value1"}, {"text": "value2"}]'
+
+    loader = JSONLoader(file_path=file_path, jq_schema=".[].text", text_content=True)
+    result = loader.load()
+
+    assert result == expected_docs
+
+
+@pytest.mark.requires("jq")
+def test_load_valid_dict_content(mocker: MockerFixture) -> None:
+    file_path = "/workspaces/langchain/test.json"
+    expected_docs = [
+        Document(
+            page_content='{"text": "value1"}',
+            metadata={"source": file_path, "seq_num": 1},
+        ),
+        Document(
+            page_content='{"text": "value2"}',
+            metadata={"source": file_path, "seq_num": 2},
+        ),
+    ]
+    mocker.patch("builtins.open", mocker.mock_open())
+    mock_csv_reader = mocker.patch("pathlib.Path.read_text")
+    mock_csv_reader.return_value = """
+        [{"text": "value1"}, {"text": "value2"}]
+    """
+
+    loader = JSONLoader(file_path=file_path, jq_schema=".[]", text_content=False)
+    result = loader.load()
+
+    assert result == expected_docs
+
+
+@pytest.mark.requires("jq")
+def test_load_valid_bool_content(mocker: MockerFixture) -> None:
+    file_path = "/workspaces/langchain/test.json"
+    expected_docs = [
+        Document(
+            page_content="False",
+            metadata={"source": file_path, "seq_num": 1},
+        ),
+        Document(
+            page_content="True",
+            metadata={"source": file_path, "seq_num": 2},
+        ),
+    ]
+    mocker.patch("builtins.open", mocker.mock_open())
+    mock_csv_reader = mocker.patch("pathlib.Path.read_text")
+    mock_csv_reader.return_value = """
+        [
+            {"flag": false}, {"flag": true}
+        ]
+    """
+
+    loader = JSONLoader(file_path=file_path, jq_schema=".[].flag", text_content=False)
+    result = loader.load()
+
+    assert result == expected_docs
+
+
+@pytest.mark.requires("jq")
+def test_load_valid_numeric_content(mocker: MockerFixture) -> None:
+    file_path = "/workspaces/langchain/test.json"
+    expected_docs = [
+        Document(
+            page_content="99",
+            metadata={"source": file_path, "seq_num": 1},
+        ),
+        Document(
+            page_content="99.5",
+            metadata={"source": file_path, "seq_num": 2},
+        ),
+    ]
+    mocker.patch("builtins.open", mocker.mock_open())
+    mock_csv_reader = mocker.patch("pathlib.Path.read_text")
+    mock_csv_reader.return_value = """
+        [
+            {"num": 99}, {"num": 99.5}
+        ]
+    """
+
+    loader = JSONLoader(file_path=file_path, jq_schema=".[].num", text_content=False)
+    result = loader.load()
+
+    assert result == expected_docs
+
+
+@pytest.mark.requires("jq")
+def test_load_invalid_test_content(mocker: MockerFixture) -> None:
+    file_path = "/workspaces/langchain/test.json"
+    mocker.patch("builtins.open", mocker.mock_open())
+    mock_csv_reader = mocker.patch("pathlib.Path.read_text")
+    mock_csv_reader.return_value = """
+        [{"text": "value1"}, {"text": "value2"}]
+    """
+
+    loader = JSONLoader(file_path=file_path, jq_schema=".[]", text_content=True)
+
+    with raises(ValueError):
+        loader.load()