blast_repo fixes (dart-archive/markdown#627)

drop-lint

Author: kevmoo

pkgs/markdown/analysis_options.yaml

@@ -26,7 +26,6 @@ linter:
     - literal_only_boolean_expressions
     - missing_whitespace_between_adjacent_strings
     - no_adjacent_strings_in_list
-    - package_api_docs
     - prefer_const_declarations
     - prefer_final_locals
     - prefer_final_in_for_each