refactor: implement generic optional import mechanisms

this project is actively using optional imports, which leads to
duplicate handling here and there. This commit implements logic in
special method to reduce complexity and simplify tests paths

ahriman-web/tests/ahriman/web/apispec/test_info.py

@@ -48,7 +48,8 @@ def test_setup_apispec(application: Application, mocker: MockerFixture) -> None:
     must set api specification
     """
     apispec_mock = mocker.patch("aiohttp_apispec.setup_aiohttp_apispec")
-    assert setup_apispec(application)
+
+    setup_apispec(application)
     apispec_mock.assert_called_once_with(
         application,
         url="/api-docs/swagger.json",

ahriman-web/tests/ahriman/web/views/v1/user/test_view_v1_user_login.py

@@ -37,7 +37,7 @@ async def test_get_import_error(client_with_auth: TestClient, mocker: MockerFixt
     """
     must return 405 on import error
     """
-    pytest.helpers.import_error("ahriman.core.auth.oauth", ["OAuth"], mocker)
+    mocker.patch("ahriman.web.views.v1.user.login.optional_module", return_value=None)
     response = await client_with_auth.get("/api/v1/login")
     assert response.status == 405