[Internal]: Automatic Import is GA

### Description

the 8.18 version of the doc still says it's in tech preview

### Resources

-

### Which documentation set does this change impact?

Elastic On-Prem and Cloud (all)

### Feature differences

-

### What release is this request related to?

8.18

### Serverless release

-

### Collaboration model

The documentation team

### Point of contact.

**Main contact:** @

**Stakeholders:**
