##### SUMMARY
win_domain_user always returns changed if a password is specified.

##### ISSUE TYPE
- Bug Report

##### COMPONENT NAME
win_domain_user

##### ANSIBLE VERSION
```paste below
ansible 2.8.1
  config file = /etc/ansible/ansible.cfg
  configured module search path = ['/home/user/.ansible/plugins/modules', '/usr/share/ansible/plugins/modules']
  ansible python module location = /usr/lib/python3.7/site-packages/ansible
  executable location = /usr/bin/ansible
  python version = 3.7.3 (default, Mar 26 2019, 21:43:19) [GCC 8.2.1 20181127]
```

##### CONFIGURATION

##### OS / ENVIRONMENT

ArchLinux

##### STEPS TO REPRODUCE
```yaml
- name: Set AD User Password
      win_domain_user:
        name: '{{ user_name }}'
        password: '{{ password }}'
        state: present
- name: Set AD User Password again
      win_domain_user:
        name: '{{ user_name }}'
        password: '{{ password }}'
        state: present
```

##### EXPECTED RESULTS
The 2nd task to show as not changed.

##### ACTUAL RESULTS
The 2nd task shows as changed, even though the password was already set.
default: replace
  password:
    description:
      - Optionally set the user's password to this (plain text) value.
      - To enable an account - I(enabled) - a password must already be
        configured on the account, or you must provide a password here.
    type: str
  update_password:
    description:
      - C(always) will update passwords if they differ.
      - C(on_create) will only set the password for newly created users.
      - Note that C(always) will always report an Ansible status of 'changed'
        because we cannot determine whether the new password differs from
        the old password.
    type: str
    choices: [ always, on_create ]
    default: always
  password_expired:
    description:
      - C(yes) will require the user to change their password at next login.
      - C(no) will clear the expired password flag.
      - This is mutually exclusive with I(password_never_expires).
    type: bool
  password_never_expires:
    description:
      - C(yes) will set the password to never expire.
      - C(no) will allow the password to expire.
      - This is mutually exclusive with I(password_expired).
    type: bool
  user_cannot_change_password: