Arguments passed via an entrypoint are going to be overridden by gitlab runner

Summary

Shell arguments passed via entrypoint will be overridden by gitlab runner.

Steps to reproduce

.gitlab-ci.yml 
stages:
  - test

test:
  stage: test
  image:
    name: debian:buster-slim
    entrypoint: ["/bin/bash", "-c", "echo $0 $@"]
  script: test arguments

Actual behavior

Shell arguments $0 $@ get the value below:

sh -c if [ -x /usr/local/bin/bash ]; then exec /usr/local/bin/bash elif [ -x /usr/bin/bash ]; then exec /usr/bin/bash elif [ -x /bin/bash ]; then exec /bin/bash elif [ -x /usr/local/bin/sh ]; then exec /usr/local/bin/sh elif [ -x /usr/bin/sh ]; then exec /usr/bin/sh elif [ -x /bin/sh ]; then exec /bin/sh elif [ -x /busybox/sh ]; then exec /busybox/sh else echo shell not found exit 1 fi
Job succeeded

Expected behavior

test arguments
Job succeeded

Relevant logs and/or screenshots

job log 
❯ gitlab-runner  exec docker --docker-privileged --docker-pull-policy="if-not-present" test
Runtime platform arch=amd64 os=darwin pid=30405 revision=54944146 version=13.10.0
Running with gitlab-runner 13.10.0 (54944146)
Preparing the "docker" executor
Using Docker executor with image debian:buster-slim ...
Using locally found image version due to "if-not-present" pull policy
Using docker image sha256:5b395270ee77958e26c38f6d64a8ae8ace5c3a5366de419baf118b042ec77ecf for debian:buster-slim with digest debian@sha256:8bf6c883f182cfed6375bd21dbf3686d4276a2f4c11edc28f53bd3f6be657c94 ...
Preparing environment
Running on runner--project-0-concurrent-0 via desktop.local...
Getting source from Git repository
Fetching changes...
Initialized empty Git repository in /builds/project-0/.git/
Created fresh repository.
Checking out d58cfdb6 as master...

Skipping Git submodules setup
Executing "step_script" stage of the job script
Using docker image sha256:5b395270ee77958e26c38f6d64a8ae8ace5c3a5366de419baf118b042ec77ecf for debian:buster-slim with digest debian@sha256:8bf6c883f182cfed6375bd21dbf3686d4276a2f4c11edc28f53bd3f6be657c94 ...
sh -c if [ -x /usr/local/bin/bash ]; then exec /usr/local/bin/bash elif [ -x /usr/bin/bash ]; then exec /usr/bin/bash elif [ -x /bin/bash ]; then exec /bin/bash elif [ -x /usr/local/bin/sh ]; then exec /usr/local/bin/sh elif [ -x /usr/bin/sh ]; then exec /usr/bin/sh elif [ -x /bin/sh ]; then exec /bin/sh elif [ -x /busybox/sh ]; then exec /busybox/sh else echo shell not found exit 1 fi
Job succeeded

Environment description

Own gitlab-runner on MacOS. But the same behaviour comes on a remote gitlab-runner as well.

config.toml contents 
concurrent = 1
check_interval = 0

[session_server]
  session_timeout = 1800

[[runners]]
  name = "runner-local"
  url = "https://xxxxx"
  token = "xxxxx"
  executor = "docker"
  [runners.docker]
    host = "tcp://docker:2375"
    tls_verify = false
    image = "docker:stable"
    privileged = true
    disable_cache = false
    shm_size = 0

Used GitLab Runner version

Version:      13.10.0
Git revision: 54944146
Git branch:   13-10-stable
GO version:   go1.16.2
Built:        2021-03-21T10:46:10+00:00
OS/Arch:      darwin/amd64
Edited by Frank Tamás