message: docs: update changelog to mention v14.0.0-rc.1 release
diff: +<a name="14.0.0-rc.1"></a>
  +
  +# 14.0.0-rc.1 (2022-05-31)
  +
  +No user-visible changes, just an RC release to test internal infrastructure changes.
  +
  +<!-- CHANGELOG SPLIT MARKER -->
  +
  <a name="14.0.0-rc.0"></a>
  # 14.0.0-rc.0 (2022-05-11)
  