[DOCS] Bulk edit rule actions

[joepeeples]

Description

Per elastic/kibana#138900, users can bulk edit actions on multiple rules.

elastic/kibana#140626 also makes some additional changes to the flyout and functionality.

Images

NOTE: UI copy is still being edited; these are preliminary images.

New item in "Bulk actions" menu:

New flyout:

Notes

• Selecting an Actions frequency applies that to all actions (both new and existing) on all selected rules. That means you can basically overwrite the frequency on existing actions, even without checking the "Overwrite all selected rules actions" box. (That checkbox appears to apply only to the actions themselves, not frequency.)
• Update rule management docs (might want to link to a new section/topic for this): https://www.elastic.co/guide/en/security/master/rules-ui-management.html#edit-rules-settings
• API docs probably also need updating: https://www.elastic.co/guide/en/security/master/bulk-actions-rules-api.html#bulk-edit-object-schema (DONE in Add Docs for Bulk Update Schedule and Rule Actions #2506)

[banderror]

elastic/kibana#140626 also makes some additional changes to the flyout and functionality.

I can expand on what we changed in this PR:

• We removed the Perform no actions option from the Actions frequency dropdown.
  • This means users will no longer be able to mute existing rule actions (this is effectively done under the hood by the app when this frequency is applied) or (if the overwrite checkbox is checked) remove all existing actions from the affected rules.
  • Users will still be able to mute actions when editing rules individually.
• Consequently, rules can no longer be muted by a bulk action under the hood. Previously, if the user selected Perform no actions we'd mute the affected rules. Now when we don't provide this option we don't need this logic in the bulk action endpoint anymore.
• FYI muting is a feature of the Alerting Framework which is not yet supported in Security Solution but is available in Stack Management. This PoC is the first step toward adding support for muting in Security Solution.