Bump tag2link from 2026.5.6 to 2026.5.21 in the dependencies group

Bump tag2link from 2026.5.6 to 2026.5.21 in the dependencies group

Bumps the dependencies group with 1 update: [tag2link](https://github.com/JOSM/tag2link).

Updates `tag2link` from 2026.5.6 to 2026.5.21
- [Release notes](https://github.com/JOSM/tag2link/releases)
- [Commits](https://github.com/JOSM/tag2link/compare/2026.5.6...2026.5.21)

---
updated-dependencies:
- dependency-name: tag2link
  dependency-version: 2026.5.21
  dependency-type: direct:production
  update-type: version-update:semver-patch
  dependency-group: dependencies
...

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