Gitlab code viewer should enable devs to click through to other classes within the same repository
<!--IssueSummary start--> <details> <summary> Everyone can contribute. [Help move this issue forward](https://handbook.gitlab.com/handbook/marketing/developer-relations/contributor-success/community-contributors-workflows/#contributor-links) while earning points, leveling up and collecting rewards. </summary> - [Close this issue](https://contributors.gitlab.com/manage-issue?action=close&projectId=278964&issueIid=342770) </details> <!--IssueSummary end--> <!-- This template is a great use for issues that are feature::additions or technical tasks for larger issues.--> ### Proposal When devs are looking at a codebase through GitLab's UI they often want to follow classes by click on them as you can do in GitHub. 1. Open https://github.com/gitlab4j/gitlab4j-api/blob/master/src/main/java/org/gitlab4j/api/AbstractApi.java 1. Click on "UrlEncoder" 1. See the Definition and References 1. Be able to click to the definition or references <!-- Consider adding related issues and epics to this issue. You can also reference the Feature Proposal Template (https://gitlab.com/gitlab-org/gitlab/-/blob/master/.gitlab/issue_templates/Feature%20proposal%20-%20detailed.md) for additional details to consider adding to this issue. Additionally, as a data oriented organization, when your feature exits planning breakdown, consider adding the `What does success look like, and how can we measure that?` section. -->
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