[Security Solution] Bring Alert Grouping Feature into GA

[stephmilovic]

Alert grouping was introduced as Technical Preview in 8.7. There are a few tasks we need to take care of before the feature reaches General Availability.

Product owner: @paulewing
Designer: ??? ask @YulNaumenko
Teams impacted: explore (@YulNaumenko), detections (@logeekal )

1. Unit test coverage

• x-pack/plugins/security_solution/public/detections/components/alerts_table/grouped_alerts.tsx

2. Bug fixes

• [Security Solution]Incorrect Total Alert count under Group alert by filter #150840
• [Security Solution] - Number of rows/pagination does not work for alert grouping #151640
• [Security Solution]Mark as Closed showing for Already Closed Alert Group #150850
• [Security Solution] Pagination broken on alerts grouping #152231
• [Security Solution]Group by Custom Field text should be Group Alert by Custom Field #150844
• [Security Solution] Enabling,Disabling Include building block alerts checkbox, On group by alerts table Navigates UI to alert charts. #150832
• [Security Solution][Grouping] No Loading placeholder when it takes time for groups to appear #150726

3. User flow fixes

• A user only has one rule and it is building block. Toggle it off, all groups disappear and query empty. You have no way to toggle it back on unless you add a new rule to bring a group back and toggle it back on. This video sort of demonstrates that, but luckily in this scenario we have other rules we can use to bring it back

  uhoh2.mov

4. Cypress tests

• [Security Solution][Grouping] Add e2e UI tests for Grouping #150666

Last. Remove beta label

• Remove BETA label from feature:
  

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