##### SUMMARY
The warning that `become` show, point to a non-existing page.

The reference: https://docs.ansible.com/ansible/become.html#becoming-an-unprivileged-user
Should be: https://docs.ansible.com/ansible/user_guide/become.html#risks-of-becoming-an-unprivileged-user

```
  msg: |-
    Failed to set permissions on the temporary files Ansible needs to create when becoming an unprivileged user (rc: 1, err: chown: changing ownership of '/var/tmp/ansible-tmp-1587201990.1515293-106086999273646/': Operation not permitted
    chown: changing ownership of '/var/tmp/ansible-tmp-1587201990.1515293-106086999273646/AnsiballZ_postgresql_db.py': Operation not permitted
    }). For information on working around this, see https://docs.ansible.com/ansible/become.html#becoming-an-unprivileged-user
```

##### ISSUE TYPE
- Bug Report

##### COMPONENT NAME
become

##### ANSIBLE VERSION
```
ansible 2.9.6
  config file = None
  configured module search path = ['/home/robertdb/.ansible/plugins/modules', '/usr/share/ansible/plugins/modules']
  ansible python module location = /usr/local/lib/python3.7/site-packages/ansible
  executable location = /usr/local/bin/ansible
  python version = 3.7.6 (default, Jan 30 2020, 09:44:41) [GCC 9.2.1 20190827 (Red Hat 9.2.1-1)]
```

##### CONFIGURATION
```
# empty.
```

##### OS / ENVIRONMENT
Controller: Fedora 31
Managed node: Ubuntu 19

##### STEPS TO REPRODUCE
I use [this](https://github.com/robertdebock/ansible-role-postgres/blob/master/tasks/main.yml#L70) role on Ubuntu 19. (Using [this](https://github.com/robertdebock/ansible-tester) code.

##### EXPECTED RESULTS
The chapter is found immediately.

##### ACTUAL RESULTS
The documentation page loads (good), but does not jump to the right chapter.
module_args['_ansible_syslog_facility'] = task_vars.get('ansible_syslog_facility', C.DEFAULT_SYSLOG_FACILITY)
        
        module_args['_ansible_selinux_special_fs'] = C.DEFAULT_SELINUX_SPECIAL_FS
        
        module_args['_ansible_string_conversion_action'] = C.STRING_CONVERSION_ACTION
        
        module_args['_ansible_socket'] = getattr(self._connection, 'socket_path')
        if not module_args['_ansible_socket']:
            module_args['_ansible_socket'] = task_vars.get('ansible_socket')
        
        module_args['_ansible_shell_executable'] = self._play_context.executable
        
        module_args['_ansible_keep_remote_files'] = C.DEFAULT_KEEP_REMOTE_FILES
        
        if self._is_become_unprivileged():  
            module_args['_ansible_tmpdir'] = None
        else:
            module_args['_ansible_tmpdir'] = self._connection._shell.tmpdir
        
        module_args['_ansible_remote_tmp'] = self.get_shell_option('remote_tmp', default='~/.ansible/tmp')
    def _execute_module(self, module_name=None, module_args=None, tmp=None, task_vars=None, persist_files=False, delete_remote_tmp=None, wrap_async=False):
        '''
        Transfer and run a module along with its arguments.
        '''
        if tmp is not None:
            display.warning('_execute_module no longer honors the tmp parameter. Action plugins'
                            ' should set self._connection._shell.tmpdir to share the tmpdir')
        del tmp  
        if delete_remote_tmp is not None: