RFR: 8318295: Update launcher help for enable-native-access

[Maurizio Cimadamore]

This simple PR updates the description of the `enable-native-access` option in the launcher properties file.

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Commit messages:
 - Initial push

Changes: https://git.openjdk.org/jdk/pull/16217/files
 Webrev: https://webrevs.openjdk.org/?repo=jdk&pr=16217&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8318295
  Stats: 2 lines in 1 file changed: 0 ins; 0 del; 2 mod
  Patch: https://git.openjdk.org/jdk/pull/16217.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/16217/head:pull/16217

PR: https://git.openjdk.org/jdk/pull/16217