##### SUMMARY

The merge of #45507 broke `update_password="on_create"` on Alpine Linux with the shadow package installed.

This does not work anymore
```yml
  - name: add users                                                                                                                                                                                                                                  
    user:
      name: "{{ item.name }}"
      comment: "{ item.comment }}"
      shell: "/bin/zsh"
      password: '*'
      update_password: on_create
   with_items:
    ....
```

After the PR, all users that have a password that is not '*' will get their password changed.

Reverting bf3e397ea7922e8bd8b8ffbc05d1aede0317d119, makes 'update_password: on_create' work as expected again.

##### ISSUE TYPE
- Bug Report

##### COMPONENT NAME
<!--- Write the short name of the module, plugin, task or feature below, use your best guess if unsure -->

lib/ansible/modules/system/user.py

##### ANSIBLE VERSION
<!--- Paste verbatim output from "ansible --version" between quotes -->
```paste below
2.8.7
```

##### CONFIGURATION
<!--- Paste verbatim output from "ansible-config dump --only-changed" between quotes -->
```paste below

```

##### OS / ENVIRONMENT
<!--- Provide all relevant information below, e.g. target OS versions, network device firmware, etc. -->

Alpine Linux

##### STEPS TO REPRODUCE
<!--- Describe exactly how to reproduce the problem, using a minimal test-case -->

<!--- Paste example playbooks or commands between quotes below -->
```yaml
  - name: add users                                                                                                                                                                                                                                  
    user:
      name: "{{ item.name }}"
      comment: "{ item.comment }}"
      shell: "/bin/zsh"
      password: '*'
      update_password: on_create
```

<!--- HINT: You can paste gist.github.com links for larger files -->

##### EXPECTED RESULTS
<!--- Describe what you expected to happen when running the steps above -->

Users that are not created does not get their password changed.

##### ACTUAL RESULTS
<!--- Describe what actually happened. If possible run with extra verbosity (-vvvv) -->

<!--- Paste verbatim command output between quotes -->
```paste below
Password "hash" changed to '*'
```

type: str
        version_added: "2.8"
notes:
  - There are specific requirements per platform on user management utilities. However
    they generally come pre-installed with the system and Ansible will require they
    are present at runtime. If they are not, a descriptive error message will be shown.
  - On SunOS platforms, the shadow file is backed up automatically since this module edits it directly.
    On other platforms, the shadow file is backed up by the underlying tools used by this module.
  - On macOS, this module uses C(dscl) to create, modify, and delete accounts. C(dseditgroup) is used to
    modify group membership. Accounts are hidden from the login window by modifying
    C(/Library/Preferences/com.apple.loginwindow.plist).
  - On FreeBSD, this module uses C(pw useradd) and C(chpass) to create, C(pw usermod) and C(chpass) to modify,
    C(pw userdel) remove, C(pw lock) to lock, and C(pw unlock) to unlock accounts.
  - On all other platforms, this module uses C(useradd) to create, C(usermod) to modify, and
    C(userdel) to remove accounts.
seealso:
- module: authorized_key
- module: group
- module: win_user
author:
- Stephen Fromm (@sfromm)
'''
EXAMPLES = r'''
- name: Add the user 'johnd' with a specific uid and a primary group of 'admin'
  user:
    name: johnd
    comment: John Doe
    uid: 1040
    group: admin
- name: Add the user 'james' with a bash shell, appending the group 'admins' and 'developers' to the user's groups