RFR: 8344800: Add W3C DTDs and XSDs to the JDK built-in Catalog

[Joe Wang]

Add DTDs and XSDs from the W3C specifications to the JDK built-in Catalog.

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Commit messages:
 - fix whitespace
 - 8344800: Add W3C DTDs and XSDs to the JDK built-in Catalog

Changes: https://git.openjdk.org/jdk/pull/22465/files
  Webrev: https://webrevs.openjdk.org/?repo=jdk&pr=22465&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8344800
  Stats: 27700 lines in 106 files changed: 27683 ins; 0 del; 17 mod
  Patch: https://git.openjdk.org/jdk/pull/22465.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/22465/head:pull/22465

PR: https://git.openjdk.org/jdk/pull/22465