Fix popover appearing on page load without being pinned

Created by: chrismwendt

Continuation of https://github.com/sourcegraph/sourcegraph/pull/36039

Fixes https://github.com/sourcegraph/sourcegraph/issues/36140 (cc @mrnugget who reported it)

Test plan

Manual

App preview:

• Web
• Storybook

Check out the client app preview documentation to learn more.