Update MITRE ATT&CK® version mentioned in the docs

[nastasha-solomon]

Description

With elastic/kibana#166536, we'll need to update the MITRE ATT&CK® version mentioned in the note at the top of the MITRE ATT&CK® coverage page. The new version is v13.1.

This change was added to 8.10.3 and 8.11, so we'll need to update the feature docs and release notes for both.

Related:

• [Security Solution] Update MITRE ATT&CK mappings to the next version kibana#166152

To-do

• Feature docs updated for 8.10 and 8.11 via Updates kibana MITRE version reference to v13.1 #3983.
• Doc'd in 8.10.3 release notes via 8.10.3 Release notes #4011
• Doc'd in 8.11 release notes via TBD - Removing this as a req for closing this issue since the feature doc updates are the highest priority items. The release notes docs will come later via the PR we open for 8.11.0 Release notes #4015.
• Serverless docs updated via https://github.com/elastic/staging-serverless-security-docs/pull/187.

cc: @banderror @dplumlee @approksiu

[nastasha-solomon]

@banderror @dplumlee will the MITRE ATT&CK® coverage page in Serverless also use v13.1?

[nastasha-solomon]

Confirmed with @dplumlee via Slack that the MITRE ATT&CK® coverage page in Serverless will be using v13.1. I'll open a separate PR against the Serverless docs to make this change.
cc: @joepeeples

[nastasha-solomon]

All feature docs updated.