fix: change the directory to download a source code (database-lab-infrastructure#13)

Description

Change the /tmp mounting to /tmp/ci_checker:/tmp/ci_checker because of security reasons in order to mount only the directory the migration checker need.

Related issue

database-lab-infrastructure#13

Examples

   sudo docker run --name dblab_ci_checker --rm -it --detach \
    --publish 2500:2500 \
    --volume /var/run/docker.sock:/var/run/docker.sock \
    --volume /tmp/ci_checker:/tmp/ci_checker \
    --volume ~/.dblab/run_ci.yaml:/home/dblab/configs/run_ci.yaml \
  registry.gitlab.com/postgres-ai/database-lab/dblab-ci-checker:240-run-ci

Checklist

• the MR description has been reviewed
• this MR contains text changes and they have been reviewed OR there are no texts changes
• this MR contains GUI/CLI changes and they have been reviewed OR there are no GUI/CLI changes
• this MR contains API changes, specifications reflect those changes and they have been reviewed OR there are no API changes