What is the bug?
When defining a new detector and selecting the "System Logs" type, the "Configure field mapping" are empty.

How can one reproduce the bug?
Steps to reproduce the behavior:

1. Go to Security Analytics>Detectors>Create detector
2. Select any index
3. Click on 'System logs':

5. See that 'Configure field mapping' is empty
6. When following the link (mappings/view?indexName=index_*&ruleTopic=linux), following message is displayed:

{"ok":false,"error":"[illegal_argument_exception] Mapper not found: [linux]"}

What is the expected behavior?
Like the other types (Azure logs for example):

Also, when following the link:
{"ok":true,"response":{"properties":{},"unmapped_index_fields":

What is your host/environment?

• OS: Centos7
• Opensearch Version: 2.7.0
• Opensearch-Dashboards Version: 2.7.0