Code Insights: Fix the "loading Sourcegraph extensions" loading message for the dashboard page

Created by: Joelkw

I see you've got some great logic to check things, but every time I load the insights page I hit the "loading extensions." I think that's both confusing to a user and very much against our goal of abstracting away that these are powered by extensions (we want you to think of insights as a separate thing than extensions; we don't want you thinking insights is a subset feature of extensions, not the least because extensions may be available to all users on any plan and insights may not be someday).

I realize I'm just changing it to the message in the other condition. If you agree that it's confusing to show users this, perhaps we should collapse the conditions?

Loom: https://www.loom.com/share/cbbc9d922b3b46dea4e6242faaee7a37