[Security][8.18] Agentless CSPM integration goes GA

[benironside]

Description

Agentless CSPM is going GA in 8.18. We need to update screenshots and remove beta labels from docs for the agentless option.

More info here: https://github.com/elastic/security-team/issues/10938

Resources

More details here: https://github.com/elastic/security-team/issues/10938

Which documentation set does this change impact?

Elastic On-Prem and Cloud (all)

Feature differences

What release is this request related to?

8.18

Collaboration model

The documentation team

Point of contact.

Main contact: @smriti0321

Stakeholders: