How to log redmine tasks with gitlab ci?

Question

Redmine

There is redmine 3, gitlab 8
In each project commit we have issue numbers: 'refs #3875'.
There are branches master, which looks at dev, and prod, which is laid out on a working project.
I want to keep a log of project updates in production.
I see it this way. For example, we do new tasks for a week, at the end we merge master and prod.
prod contains 10 new comedians and is automatically deployed to the production server. At the same time, the task numbers from the merge request are collected, the titles of these tasks are pulled up by the numbers from the redmine and written to some kind of log file.
I don’t ask you to write scripts for me, but I ask you to help me navigate and in which direction to dig