While debugging a sentry error for "ActiveRecord::InvalidForeignKey ActiveStorage::Representations::RedirectController", it was noticed that we enqueue a Avatar::AvatarFromUrlJob for each setUser call, which is unnecessary. Hence making this call only if the contact doesn't have an existing avatar.
If one needs to have this avatar updated, they can go to the contacts tab and delete the current avatar, Chatwoot will pick up the new avatar in subsequent API call.
fixes: #3853
- Introduced DISABLE_GRAVATAR Global Config, which will stop chatwoot from making API requests to gravatar
- Cleaned up avatar-related logic and centralized it into the avatarable concern
- Added specs for the missing cases
- Added migration for existing installations to move the avatar to attachment, rather than making the API that results in 404.
