[Security Solution] Rule execution marked as failed when the rule is modified meanwhile is executed

[MadameSheema]

Describe the bug:
Rule execution fails when the rule is modified meanwhile is executed. This is more likely to happen with rules that takes time to be processed.

Kibana/Elasticsearch Stack version:

• 7.10.0 - BC4

Initial status:

• To have an indicator match rule created with a big look-back time (i.e. 30000 hours) and a small execution time (i.e. 10 seconds)

Steps to reproduce:

1. Edit the existing adding a new Indicator Index Pattern
2. Save the changes
3. Wait for the rule to be executed

Current behavior:

Expected behavior:

• No error message is displayed

Additional information:

• The rule seems to recover well and to execute properly but the error message is still visible for the user
• Although the execution of the rule is successful, when you deactivate the rule the rule is marked as failed.

[peluja1012]

We think this might be resolved by this Alerting PR #80149

[spong]

Since #80149 isn't targeted for 7.10.1 and a fix won't be available to users till 7.11 we'll want to either add a note to our documentation outlining this behavior (and workaround of disabling/checking rule isn't running before editing) and/or reference it in known issues for this release (although technically this is pre-existing so inline in docs might be best).

cc @jmikell821 @Donnater