[jdk17u-dev] RFR: 8305962: update jcstress to 0.16

[Aleksey Shipilev]

Clean backport to make [JDK-8323717](https://bugs.openjdk.org/browse/JDK-8323717) backport clean. I had to resolve copyright years in `TestGenerator.java`.

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Commit messages:
 - Backport 292ee630ae32c3b50363b10ffa6090e57ffef1e8

Changes: https://git.openjdk.org/jdk17u-dev/pull/2234/files
 Webrev: https://webrevs.openjdk.org/?repo=jdk17u-dev&pr=2234&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8305962
  Stats: 64 lines in 5 files changed: 53 ins; 0 del; 11 mod
  Patch: https://git.openjdk.org/jdk17u-dev/pull/2234.diff
  Fetch: git fetch https://git.openjdk.org/jdk17u-dev.git pull/2234/head:pull/2234

PR: https://git.openjdk.org/jdk17u-dev/pull/2234