##### SUMMARY
`esc_period` is mandatory even with `state: absent` - should be optional in that case.

##### ISSUE TYPE
- Bug Report

##### COMPONENT NAME
zabbix_action

##### ANSIBLE VERSION
latest

##### CONFIGURATION
Not relevant.

##### OS / ENVIRONMENT
Not relevant.

##### STEPS TO REPRODUCE
```yaml
  - name: "Report problems to Zabbix administrators"
    event_source: 'trigger'
    state: absent
```

##### EXPECTED RESULTS
Action, if exists, is removed.

##### ACTUAL RESULTS
```paste below
"msg": "missing required arguments: esc_period"
```
"""Construct operation message user.
        Args:
            operation: operation to construct the message user
        Returns:
            list: constructed operation message user or None if operation not found
        """
        if operation.get('send_to_users') is None:
            return None
        return [{
            'userid': self._zapi_wrapper.get_user_by_user_name(_user)['userid']
        } for _user in operation.get('send_to_users')]
    def _construct_opmessage_grp(self, operation):
        """Construct operation message group.
        Args:
            operation: operation to construct the message group
        Returns:
            list: constructed operation message group or None if operation not found
        """
        if operation.get('send_to_groups') is None:
            return None
        return [{
            'usrgrpid': self._zapi_wrapper.get_usergroup_by_usergroup_name(_group)['usrgrpid']
        } for _group in operation.get('send_to_groups')]
    def _construct_opcommand(self, operation):