UI Update: Notifications editor

[gschueler]

Is this a bugfix, or an enhancement? Please describe.

Replace old form field mechanism with Vue components.

Describe the solution you've implemented

• Vue UI to edit notifications
• existing notification data is passed as json to the Vue (edit existing job)
• Notification data is stored as json in a single form field
• json data is inflated when constructing job definition
• Adds two "dummy" plugins for the email/webhooks builtin notification types, allowing normal plugin UI generation to be driven by them
  • the email/webhook notification implementation still happens through the builtin code (todo: move this to plugins themselves)
• added undo/redo feature

Additional context

Old form based method was very old, and hit a Jetty limit of 1000 form fields(!) in some recent enterprise tests.

Enable new Vue method using feature flag rundeck.feature.notificationsEditorVue.enabled=true

Todos

• Refine UI design
• Fix issue in Vue code: Ace editor not loading correctly for display/editing of plugin config properties
• remove old form-based code completely (gsp views, backend parsing/validation)