JetBrains: Remove “Sourcegraph” menu from “Find Actions” list

Created by: vdavid

Fixes https://github.com/sourcegraph/sourcegraph/issues/37994

Just removed the “Sourcegraph” menu. It added clutter because the user couldn’t tell what it did (based on the user tests), and all the other options were already there.

Test plan

Tested, this is the only thing that changed (the “Sourcegraph” menu is gone):

App preview:

• Web
• Storybook

Check out the client app preview documentation to learn more.