Play Framework

docs: repair three dangling documentation links

Found by resolving every textile cross-link against the filesystem the way
docviewer + the browser actually resolve them (relative to the linking
page's own URL), then discarding false positives by reading the routes.

- releasenotes-1.12.0: pointed at documentation/assessments/PF-89-junit-6-upgrade.md,
  purged by PF-90 in 358e7e2ba. Now cites the audit's commit (596e64a3f)
  instead of a path that no longer resolves — same treatment applied to
  framework/dependencies.yml in f304ba9e9.
- samples.textile: linked releasenotes-1.12.x; the file is releasenotes-1.12.0.
- releasenotes-1.0.3: 'Next release' linked releasenotes-1.1 as a sibling, but
  that page lives in ../release1.1.x/, so the browser resolved it inside
  release1.0.x/ and 404'd.

Verified: no reference to the purged assessment remains anywhere, and every
documentation/ path cited in a tracked file now resolves.

Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>