[SLO] Use recommended burn rate configuration in the Burn Rate Create rule form

[mgiota]

🍒 Summary

As an effort to improve and simplify the SLO Burn rate rule creation experience, we would like to show by default a toggle that says "Use recommended burn rate windows and threshold" (or maybe "Use recommended burn rate rule configuration"). Then allow users to customize the configuration (windows, burn rates or budget consumption)

✅ Acceptance criteria

• By default use the recommended burn rate windows
• Show a toggle that allows user to customize the configuration for multiple windows (lookback windows, burn rates (or/and budget consumption), action groups)
• User should be able to add/delete windows

[elasticmachine]

Pinging @elastic/actionable-observability (Team: Actionable Observability)

[elasticmachine]

Pinging @elastic/obs-ux-management-team (Team:obs-ux-management)

[jasonrhodes]

@mgiota I think we have evolved the burn rate to start with recommended values, right? Feel free to re-open this if I'm mistaken or if we want to do more.