Fix deprecation warnings from test run

[nigini]

All tests passed, but there are a bunch of deprecation warnings to be tackled:

========================================================================== warnings summary ===========================================================================
../../VENV/ublog/lib/python3.10/site-packages/pydantic/main.py:1069
tests/test_outbox.py::test_send_create_activity__with_attachment
tests/test_outbox.py::test_send_create_activity__with_attachment
tests/test_outbox.py::test_send_create_activity__no_content_with_cw_and_attachments
  ../../VENV/ublog/lib/python3.10/site-packages/pydantic/main.py:1069: PydanticDeprecatedSince20: The `parse_obj` method is deprecated; use `model_validate` instead. Deprecated in Pydantic V2.0 to be removed in V3.0. See Pydantic V2 Migration Guide at https://errors.pydantic.dev/2.6/migration/
    warnings.warn(

app/database.py:26
  /home/./microblog.pub/app/database.py:26: MovedIn20Warning: Deprecated API features detected! These feature(s) are not compatible with SQLAlchemy 2.0. To prevent incompatible upgrades prior to updating applications, ensure requirements files are pinned to "sqlalchemy<2.0". Set environment variable SQLALCHEMY_WARN_20=1 to show all deprecation warnings.  Set environment variable SQLALCHEMY_SILENCE_UBER_WARNING=1 to silence this message. (Background on SQLAlchemy 2.0 at: https://sqlalche.me/e/b8d9)
    Base: Any = declarative_base()

../../VENV/ublog/lib/python3.10/site-packages/pydantic/_internal/_config.py:272
 ../../VENV/ublog/lib/python3.10/site-packages/pydantic/_internal/_config.py:272: PydanticDeprecatedSince20: Support for class-based `config` is deprecated, use ConfigDict instead. Deprecated in Pydantic V2.0 to be removed in V3.0. See Pydantic V2 Migration Guide at https://errors.pydantic.dev/2.6/migration/
    warnings.warn(DEPRECATION_MESSAGE, DeprecationWarning)

../../VENV/ublog/lib/python3.10/site-packages/starlette/templating.py:102
  ../../VENV/ublog/lib/python3.10/site-packages/starlette/templating.py:102: DeprecationWarning: Extra environment options are deprecated. Use a preconfigured jinja2.Environment instead.
    warnings.warn(

tests/test_actor.py: 1 warning
tests/test_httpsig.py: 3 warnings
tests/test_ldsig.py: 1 warning
tests/test_process_outgoing_activities.py: 6 warnings
  sys:1: SAWarning: Can't sort tables for DROP; an unresolvable foreign key dependency exists between tables: inbox, outbox; and backend does not support ALTER.  To restore at least a partial sort, apply use_alter=True to ForeignKey and ForeignKeyConstraint objects involved in the cycle to mark these as known cycles that will be ignored.

tests/test_actor.py: 1 warning
tests/test_admin.py: 1 warning
tests/test_emoji.py: 3 warnings
tests/test_httpsig.py: 2 warnings
tests/test_inbox.py: 9 warnings
tests/test_outbox.py: 11 warnings
tests/test_process_outgoing_activities.py: 1 warning
tests/test_public.py: 13 warnings
tests/test_remote_actor_deletion.py: 2 warnings
tests/test_tags.py: 2 warnings
  /home/./microblog.pub/tests/conftest.py:33: SAWarning: Can't sort tables for DROP; an unresolvable foreign key dependency exists between tables: inbox, outbox; and backend does not support ALTER.  To restore at least a partial sort, apply use_alter=True to ForeignKey and ForeignKeyConstraint objects involved in the cycle to mark these as known cycles that will be ignored.
    Base.metadata.drop_all(bind=engine)

tests/test_emoji.py: 1 warning
tests/test_outbox.py: 10 warnings
tests/test_tags.py: 1 warning
  ../../VENV/ublog/lib/python3.10/site-packages/httpx/_client.py:799: DeprecationWarning: Setting per-request cookies=<...> is being deprecated, because the expected behaviour on cookie persistence is ambiguous. Set cookies directly on the client instance instead.
    warnings.warn(message, DeprecationWarning)

tests/test_emoji.py::test_emoji_note_with_emoji
tests/test_public.py::test_index__html
tests/test_public.py::test_followers__html
tests/test_public.py::test_followers__html_hides_followers
tests/test_public.py::test_following__html
tests/test_public.py::test_following__html_hides_following
tests/test_tags.py::test_tags__note_with_tag
  ../../VENV/ublog/lib/python3.10/site-packages/starlette/templating.py:178: DeprecationWarning: The `name` is not the first parameter anymore. The first parameter should be the `Request` instance.
  Replace `TemplateResponse(name, {"request": request})` by `TemplateResponse(request, name)`.
    warnings.warn(

tests/test_process_outgoing_activities.py::test_process_next_outgoing_activity__connect_error
  ../../VENV/ublog/lib/python3.10/site-packages/factory/alchemy.py:127: SAWarning: Identity map already had an identity for (<class 'app.models.OutboxObject'>, (1,), None), replacing it with newly flushed object.   Are there load operations occurring inside of an event handler within the flush?
    session.commit()

tests/test_process_outgoing_activities.py::test_process_next_outgoing_activity__connect_error
  ../../VENV/ublog/lib/python3.10/site-packages/factory/alchemy.py:127: SAWarning: Identity map already had an identity for (<class 'app.models.OutgoingActivity'>, (1,), None), replacing it with newly flushed object.   Are there load operations occurring inside of an event handler within the flush?
    session.commit()

-- Docs: https://docs.pytest.org/en/stable/how-to/capture-warnings.html