How to modify the migration step in auto devops

I’m using gitlab auto devops in my project (hosted free on
I have followed the migration job in the deploy stage.
I understand that gitlab auto devops execute the command specified in the env var inside my app container.

I am managing sql scripts which I want to run on every migration.
For instance, I want to use a postgres image and execute psql -f myscript.sql.
The script is in the project repository, so changing the image in the helm chart didn’t help since the script is not there.

I don’t want to modify the gitlab-ci.yml but I do need to modify the deploy stage some way.
What do you suggest that I can do?