Explicitly use a filter when extracting Gramps tar files, and be less…

… trusting of such archives (#1525)

betty/gramps/loader.py

@@ -197,7 +197,7 @@ async def load_gpkg(self, gpkg_path: Path) -> None:
                 async with TemporaryDirectory() as cache_directory_path_str:
                     tarfile.open(
                         fileobj=tar_file,
-                    ).extractall(cache_directory_path_str)
+                    ).extractall(cache_directory_path_str, filter="data")
                     await self.load_gramps(
                         Path(cache_directory_path_str) / "data.gramps"
                     )