##### 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"
```
], True],
                    ['command_type', 'custom_script', [
                        'command',
                        'execute_on'
                    ]],
                    ['command_type', 'ipmi', ['command']],
                    ['command_type', 'ssh', [
                        'command',
                        'password',
                        'username',
                        'port',
                        'ssh_auth_type',
                        'ssh_privatekey_file',
                        'ssh_publickey_file'
                    ]],
                    ['command_type', 'telnet', [
                        'command',
                        'password',
                        'username',
                        'port'
                    ]],
                    ['command_type', 'global_script', ['script_name']],
                    ['type', 'send_message', ['send_to_users', 'send_to_groups'], True]
                ]
            ),
            acknowledge_operations=dict(
                type='list',
                required=False,
                default=[],
                elements='dict',