Add (back) the ability to share links to code intel popover locations 2

Created by: chrismwendt

• https://github.com/sourcegraph/sourcegraph/pull/35658 original
• https://github.com/sourcegraph/sourcegraph/pull/36025 revert
• This PR fixes:
  • Border didn't extend all the way across the popover https://github.com/sourcegraph/sourcegraph/pull/35658#issuecomment-1137054057
  • Hovering or clicking would cause a scroll
  • Changed text to "Copied!" for a few seconds for visual feedback https://sourcegraph.slack.com/archives/CHXHX7XAS/p1653469155353199

Add (back) the ability to share links to code intel popover locations

(note from Chris) There's a tiny 🐛 remaining: using browser back/forward to add/remove the ?popover=pinned URL param should also show/hide the popover, but it currently remains hidden. If anyone finds this annoying, we can dig further to and fix it.

Resolves #30698 (closed)

Test plan

Manual

App preview:

• Web
• Storybook

Check out the client app preview documentation to learn more.