Fix internal link

ideas.md

@@ -3,7 +3,7 @@
 **Table of Contents**  *generated with [DocToc](https://github.com/thlorenz/doctoc)*
 - [Proposal ideas](#proposal-ideas)
-  - [Internationalization / translations](#internationalization--translations)
+  - [Internationalization / translations](#internationalization-translations)
   - [Mailing list functionality](#mailing-list-functionality)
   - [Transactional merge request comments](#transactional-merge-request-comments)
   - [Cross-server (federated) merge requests](#cross-server-federated-merge-requests)
@@ -25,7 +25,7 @@ Below are some ideas to get you started. The list is not exhaustive, you are
 encouraged to take a look at [GitLab's direction page](https://about.gitlab.com/direction/)
 for more items.
-## Internationalization / translations
+## Internationalization - translations
 - **Relevant Issue:** https://gitlab.com/gitlab-org/gitlab-ce/issues/4012
 - **Skills:** Rails