Add missing mock in aemet config flow tests (#89360)

tests/components/aemet/conftest.py

@@ -0,0 +1,14 @@
+"""Test fixtures for aemet."""
+from collections.abc import Generator
+from unittest.mock import AsyncMock, patch
+
+import pytest
+
+
+@pytest.fixture
+def mock_setup_entry() -> Generator[AsyncMock, None, None]:
+    """Override async_setup_entry."""
+    with patch(
+        "homeassistant.components.aemet.async_setup_entry", return_value=True
+    ) as mock_setup_entry:
+        yield mock_setup_entry