RFR: 8358602: JFR: Annotations in jdk.jfr package should not use "not null" in specification

[Erik Gahlin]

Could I have review of PR that fixes the specification / documentation for annotations in the jdk.jfr package.

Testing: tier1 + jdk/jdk/jfr

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Commit messages:
 - Initial

Changes: https://git.openjdk.org/jdk/pull/25723/files
  Webrev: https://webrevs.openjdk.org/?repo=jdk&pr=25723&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8358602
  Stats: 15 lines in 8 files changed: 0 ins; 0 del; 15 mod
  Patch: https://git.openjdk.org/jdk/pull/25723.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/25723/head:pull/25723

PR: https://git.openjdk.org/jdk/pull/25723