RFR: Changes due to stabilization branches

[Jesper Wilhelmsson]

As we move to stabilization branches instead of making a stabilization repo, some updates are needed.

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Commit messages:
 - Updates due to stabilization branches
 - Minor bug fixes

Changes: https://git.openjdk.org/guide/pull/123/files
  Webrev: https://webrevs.openjdk.org/?repo=guide&pr=123&range=00
  Stats: 39 lines in 9 files changed: 11 ins; 1 del; 27 mod
  Patch: https://git.openjdk.org/guide/pull/123.diff
  Fetch: git fetch https://git.openjdk.org/guide.git pull/123/head:pull/123

PR: https://git.openjdk.org/guide/pull/123