Summary:
- Preserving cursor position when linked state is removed.
- Moving linking tests to grist core.
- Disabling yarn offline mirror for grist-core. This helps testing grist-core when it is imported as a submodule.
- Moving one test for linked section from ReferenceColumns.ts to RightPanelSelectBy.ts.
Test Plan: Updated
Reviewers: paulfitz
Reviewed By: paulfitz
Subscribers: paulfitz
Differential Revision: https://phab.getgrist.com/D3795
