Fix link in collaboration documentation

[eswarclynn]

Describe what your pull request does. If appropriate, add GIFs or images showing the before and after.

Change Type

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

• [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

Test Plan

1. Add a step-by-step description of how to test your PR here.

• [ ] Unit Tests
• [ ] End to end tests

Release Notes

• Add a brief release note for your PR here.

[vercel[bot]]

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[huppy-bot[bot]]

eswarclynn has signed the Contributor License Agreement. Thanks!

[eswarclynn]

I have read and agree to the Contributor License Agreement.

[mimecuvalo]

thank you!