Fix istio importer by skipping  UI metadata files.
@@ -58,6 +58,11 @@ class IstioDataSource(GitDataSource):
files = self._added_files.union(self._updated_files)
advisories = []
for f in files:
+ # Istio website has files with name starting with underscore, these contain metadata
+ # required for rendering the website. We're not interested in these.
+ # See also https://github.com/nexB/vulnerablecode/issues/563
+ if f.endswith("_index.md"):
+ continue
processed_data = self.process_file(f)
if processed_data:
advisories.extend(processed_data)
