Include pdf filenames into zuul config

Zuul jobs expect to know PDF filenames to be fetching from artifacts.
Best way is to include them into the project config while managing zuul
config.

tools/update_zuul_project_configs.py

@@ -161,7 +161,7 @@ def process_repositories(args, service):
                 doc_type = doc["type"]
             # Collect all PDF files into sphinx_pdf_files var
             pdf_name = doc.get('pdf_name')
-            if pdf_name and f"{pdf_name}.pdf" not in sphinx_pdf_files:
+            if pdf_name and pdf_name not in sphinx_pdf_files:
                 sphinx_pdf_files.append(f"{pdf_name}.pdf")
                 zuul_config_updated = True