Postgres version missmatch

I just tried to update my Docker GitLab-CE instance to the newest version 12.10.1, but it fails during the migration process of the reconfigure command. It says I have a PostgreSQL version mismatch between my "external" Postgres server (Docker image version 10.3) and pg_dump inside the container (9.6). I am very confused by this behavior since I am running GitLab with the same Postgres 10 Docker image very successful for more than a year now. I did not change anything at my postgres server. Today I only pulled the newest GitLab docker image and received this error.

pg_dump: server version: 10.3 (Debian 10.3-1.pgdg90+1); pg_dump version: 9.6.17

I logged into the GitLab container and verified that it is using the "correct" pg_dump: /opt/gitlab/embedded/bin/pg_dump

Can it be that for some reason the wrong pg_dump version is installed in the latest GitLab docker image?