Update Service Account in UI

Background

Service Accounts are non-human users that serve integration needs. A user needs the ability to modify certain aspects of the service accounts, such as scope, name, and expiration date.

Why

Naming conventions change, scopes are added/removed depending on what the bot is doing, and modifying expiration date so that the bot doesn't break.

Implementation

• Re-populate inputs with existing service account name and username.
• Surface form validation error messages on submit
• Should be an addition to the efforts done in Create New Service Account (#509870 - closed) • Fernando Cardenas • 17.11 • On track
• Unit tests