RFR: 8308369: Default decomposition mode in Collator

[Naoto Sato]

Amending the description about the default decomposition mode in `Collator.NO_DECOMPOSITION` javadoc.

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Commit messages:
 - 8308369: Default decomposition mode in Collator

Changes: https://git.openjdk.org/jdk/pull/14049/files
 Webrev: https://webrevs.openjdk.org/?repo=jdk&pr=14049&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8308369
  Stats: 1 line in 1 file changed: 0 ins; 0 del; 1 mod
  Patch: https://git.openjdk.org/jdk/pull/14049.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/14049/head:pull/14049

PR: https://git.openjdk.org/jdk/pull/14049