Redmine integration plugin broken with upgrade from 9.2.1-ee to 9.5.0-ee.

Summary

After upgrading to GitLab Enterprise Edition from 9.2.1-ee to 9.5.0-ee, Redmine integration no longer works. This was working for us prior to upgrade.

Steps to reproduce

1. In a project, enable and configure Redmine integration and save

• Active: Checked
• Trigger: Checked
• Description: Redmine issue tracker
• Project url: https://www.redmine.org/projects/redmine/issues
• Issues url: https://www.redmine.org/issues/:id
• New issue url: https://www.redmine.org/projects/redmine/issues/new

2. Create a commit or merge request with #1234 in the comments.

Example Project

https://gitlab.com/tleish/redmine-integration

Redmine plugin is configured with following settings:

• Active: Checked
• Tricker: Checked
• Description: Redmine issue tracker
• Project url: https://www.redmine.org/projects/redmine/issues
• Issues url: https://www.redmine.org/issues/:id
• New issue url: https://www.redmine.org/projects/redmine/issues/new

Commit with Redmine ticket number in it: "Add readme.md for issue #1234", where #1234 should be a hyperlink to Redmine. https://gitlab.com/tleish/redmine-integration/commit/8c0f085a8e964eb20e80ed9428341f2eaa5b0d6f

What is the current bug behavior?

• No Redmine hyperlinks
• Issue tab goes to Gitlab Issues
• New Issue button/links go to Gitlab Issue

What is the expected correct behavior?

• Gitlab to convert #[issue_number] in comments to Redmine hyperlink
• Issue tab goes to Redmine Issues
• New Issue button/links go to Redmine Issue

Output of checks

• This bug happens on GitLab Enterprise Edition 9.5.0-ee
• This bug happens on GitLab.com

Additional Notes:

Previous version was 9.2.1-ee, so it's not clear which version may have broken this.