RFR: 8348975: Broken links in the JDK 24 JavaDoc API documentation, build 33

[Nizar Benalla]

Two groups of broken links appeared in the latest JDK docs, broken links to man pages and broken ietf links.

- The windows tools markdown files were not being converted to HTML because they were placed under `windows/man` rather than `share/man`, I've updated `Modules.gmk` to pick up their location.

- Contacted ietf, these are the new links to use.

This patch needs to be backported to JDK 24 as the windows tools man pages are not generated there either.

Note: the change to `ExtLinksJdk.txt` is because we partly use it to check external links, so it needs to be updated alongside the docs.

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Commit messages:
 - - fix broken ietf links

Changes: https://git.openjdk.org/jdk/pull/23351/files
  Webrev: https://webrevs.openjdk.org/?repo=jdk&pr=23351&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8348975
  Stats: 15 lines in 7 files changed: 0 ins; 1 del; 14 mod
  Patch: https://git.openjdk.org/jdk/pull/23351.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/23351/head:pull/23351

PR: https://git.openjdk.org/jdk/pull/23351