##### 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"
```
timeout = module.params['timeout']
    name = module.params['name']
    esc_period = module.params['esc_period']
    event_source = module.params['event_source']
    state = module.params['state']
    status = module.params['status']
    pause_in_maintenance = module.params['pause_in_maintenance']
    default_message = module.params['default_message']
    default_subject = module.params['default_subject']
    recovery_default_message = module.params['recovery_default_message']
    recovery_default_subject = module.params['recovery_default_subject']
    acknowledge_default_message = module.params['acknowledge_default_message']
    acknowledge_default_subject = module.params['acknowledge_default_subject']
    conditions = module.params['conditions']
    formula = module.params['formula']
    eval_type = module.params['eval_type']
    operations = module.params['operations']
    recovery_operations = module.params['recovery_operations']
    acknowledge_operations = module.params['acknowledge_operations']
    try:
        zbx = ZabbixAPI(server_url, timeout=timeout, user=http_login_user,
                        passwd=http_login_password, validate_certs=validate_certs)
        zbx.login(login_user, login_password)
        atexit.register(zbx.logout)
    except Exception as e:
        module.fail_json(msg="Failed to connect to Zabbix server: %s" % e)
    zapi_wrapper = Zapi(module, zbx)
    action = Action(module, zbx, zapi_wrapper)
    action_exists = zapi_wrapper.check_if_action_exists(name)
    ops = Operations(module, zbx, zapi_wrapper)