code monitoring: add feature flag for webhooks
Created by: limitedmage
Part of #27163 (closed)
Adds experimentalFeatures.codeMonitoringWebHooks
. When enabled, this will show the UI to configure and modify webhook and Slack actions for code monitors.
This PR also refactors the action UI used for email actions so it can be shared between the two new actions being added. The webhook and slack actions have dummy UI for now.