Remove unused hassfest helper (#82123)

script/hassfest/manifest_helper.py

@@ -1,13 +0,0 @@
-"""Helpers to deal with manifests."""
-import json
-import pathlib
-
-component_dir = pathlib.Path("homeassistant/components")
-
-
-def iter_manifests():
-    """Iterate over all available manifests."""
-    manifests = [
-        json.loads(fil.read_text()) for fil in component_dir.glob("*/manifest.json")
-    ]
-    return sorted(manifests, key=lambda man: man["domain"])