clipboard: fix copy/paste bad typo, ugh (#4008)

omg, now this typo broke older versions of Firefox, christ.
followup to https://github.com/tldraw/tldraw/pull/4003

### Change Type

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- [x] `sdk` — Changes the tldraw SDK
- [ ] `dotcom` — Changes the tldraw.com web app
- [ ] `docs` — Changes to the documentation, examples, or templates.
- [ ] `vs code` — Changes to the vscode plugin
- [ ] `internal` — Does not affect user-facing stuff

<!-- ❗ Please select a 'Type' label ❗️ -->

- [x] `bugfix` — Bug fix
- [ ] `feature` — New feature
- [ ] `improvement` — Improving existing features
- [ ] `chore` — Updating dependencies, other boring stuff
- [ ] `galaxy brain` — Architectural changes
- [ ] `tests` — Changes to any test code
- [ ] `tools` — Changes to infrastructure, CI, internal scripts,
debugging tools, etc.
- [ ] `dunno` — I don't know

### Release Notes

- Clipboard: fix copy/paste for older versions of Firefox

packages/tldraw/src/lib/ui/hooks/useClipboardEvents.ts

@@ -546,7 +546,7 @@ const handleNativeOrMenuCopy = async (editor: Editor) => {
 				}),
 			])
 		} else if (navigator.clipboard.writeText) {
-			navigator.clipboard.writeText(`<div data-tldraw>${stringifiedClipboard}</div data-tldraw>`)
+			navigator.clipboard.writeText(`<div data-tldraw>${stringifiedClipboard}</div>`)
 		}
 	}
 }