Potential fix for code scanning alert no. 35: Unused local variable

Co-authored-by: Copilot Autofix powered by AI <62310815+github-advanced-security[bot]@users.noreply.github.com>

Author: Danielhiversen

tibber/data_api.py

@@ -179,7 +179,7 @@ async def _read_error_response(self, response: aiohttp.ClientResponse) -> tuple[
             try:
                 error_data = await response.json()
             except (aiohttp.ContentTypeError, ValueError):
-                error_data = {}
+                pass
             else:
                 preferred_detail = (
                     error_data.get("detail") or error_data.get("error_description") or error_data.get("error")