Remove contribution type topics from Hacktoberfest

These make little sense, as Hacktoberfest only tracks PRs submitted by contributors, not issues. If folks want to look at issues for Hacktoberfest, they should look at issues in repositories with the  topic, not the arbitrary  topic

For both topics, there are essentially no repositories using them, with both only returning 2 repositories in their results.

Author: MattIPv4

topics/hacktoberfest/index.md

@@ -16,8 +16,5 @@ aliases: hacktoberfest-contributions, hacktoberfest-repo, hacktoberfest-contribu
 # By country
 [🇳🇵 Nepal](https://github.com/topics/hacktoberfestnepal) • [🇮🇩 Indonesia](https://github.com/topics/hacktoberfest-indonesia) • **[🇮🇳 India](https://github.com/topics/hacktoberfest-india)** ([West Bengal](https://github.com/topics/hacktoberfest-westbengal)) • [🇧🇷 Brazil](https://github.com/topics/hacktoberfest-brasil)
 
-# By contribution type
-[Issue](https://github.com/topics/hacktoberfest-issue) • [Pull Request](https://github.com/topics/hacktoberfest-pr)
-
 # By programming language
 [React.js](https://github.com/topics/react-hacktoberfest) ([topic](https://github.com/topics/react)) • [Python](https://github.com/topics/hacktoberfestpy) ([topic](https://github.com/topics/python)) • [Java](https://github.com/topics/hacktoberfest-java) ([topic](https://github.com/topics/java))