📝 Document .in_() method (#619)

* Document IN()

* Update "includes" and "tip" formatting in `where.md`

* Fix code block formatting in `where.md`

* Fix link in `where.md`

* Rename code example, add `_py310` version

---------

Co-authored-by: Motov Yurii <109919500+YuriiMotov@users.noreply.github.com>
Co-authored-by: Yurii Motov <yurii.motov.monte@gmail.com>

tests/test_tutorial/test_where/test_tutorial006b.py

@@ -0,0 +1,35 @@
+import importlib
+from types import ModuleType
+
+import pytest
+from sqlmodel import create_engine
+
+from ...conftest import PrintMock, needs_py310
+
+
+@pytest.fixture(
+    name="mod",
+    params=[
+        pytest.param("tutorial006b_py39"),
+        pytest.param("tutorial006b_py310", marks=needs_py310),
+    ],
+)
+def get_module(request: pytest.FixtureRequest) -> ModuleType:
+    mod = importlib.import_module(f"docs_src.tutorial.where.{request.param}")
+    mod.sqlite_url = "sqlite://"
+    mod.engine = create_engine(mod.sqlite_url)
+    return mod
+
+
+def test_tutorial(print_mock: PrintMock, mod: ModuleType):
+    mod.main()
+    assert print_mock.calls == [
+        [
+            {
+                "name": "Deadpond",
+                "secret_name": "Dive Wilson",
+                "age": None,
+                "id": 1,
+            }
+        ]
+    ]