gitlab-runner returns "Job succeeded" although script failed

Summary

gitlab-runner returns "Job succeeded". However, my PowerShell script failed.

Steps to reproduce

1. We remove a directory that we have not permission in PowerShell script.
2. Powershell script occurs "PermissionDenied: (db:FileInfo) [Remove-Item], UnauthorizedAccessException"
3. However, this job returns "Job succeeded".

.gitlab-ci.yml

variables:
  WORKING_DIR: C:\xx\xxxx

stages:
  - clean

clean:
  stage: clean
  tags:
    - xxxx
  script:
    - Remove-Item ${WORKING_DIR} -Recurse -Force
    - New-Item ${WORKING_DIR} -ItemType Directory

Actual behavior

1. We remove a directory that we have not permission in PowerShell script.
2. Powershell script occurs "PermissionDenied: (xx:FileInfo) [Remove-Item], UnauthorizedAccessException"
3. However, this job returns "Job succeeded".

Expected behavior

If PowerShell script occurs error, gitlab-runner returns "ERROR: Job failed: exit status x"

Relevant logs and/or screenshots

job log

Running with gitlab-runner 12.1.0 (xxxxx)
  on tests xxxxxx
Using Shell executor...
Running on xxxxx...
Fetching changes...
Reinitialized existing Git repository in C:/xxxx/.git/
From https://xxxxxx
   xxxxx..xxxxx  master     -> origin/master
Checking out xxxx as master...
git-lfs/2.7.2 (GitHub; windows amd64; go 1.12.2; git xxxxx)

Skipping Git submodules setup
$ Remove-Item ${WORKING_DIR} -Recurse -Force
Remove-Item : ���� C:\xx\xxxx\xxxx\xxxx ���폜�ł��܂���: �p�X 'xx' 
�ւ̃A�N�Z�X�����ۂ����܂����B
�����ꏊ C:\Windows\TEMP\build_script740801162\script.ps1:163 ����:1
+ Remove-Item ${WORKING_DIR} -Recurse -Force
+ ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
    + CategoryInfo          : PermissionDenied: (xx:FileInfo) [Remove-Item], U 
   nauthorizedAccessException
    + FullyQualifiedErrorId : RemoveFileSystemItemUnAuthorizedAccess,Microsoft 
   .PowerShell.Commands.RemoveItemCommand


Job succeeded

Environment description

config.toml contents

concurrent = 2
check_interval = 0

[session_server]
  session_timeout = 1800

[[runners]]
  name = "xxxxxx"
  url = "https://xxxxxx/"
  token = "xxxxx"
  executor = "shell"
  shell = "powershell"
  [runners.custom_build_dir]
  [runners.cache]
    [runners.cache.s3]
    [runners.cache.gcs]
  [runners.custom]
    run_exec = ""

Used GitLab Runner version

Running with gitlab-runner 12.1.0 (xxxxx)
  on tests My-PC