[jdk17u-dev] RFR: 8278766: Enable OpenJDK build support for reproducible jars and jmods using --date

[Andrew Leonard]

This PR is to enable usage of the --date option for OpenJDK build to enable reproducible build jars & jmods.

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Commit messages:
 - Backport 214f98f6b07e312e6f4ded5364a94277114784e7

Changes: https://git.openjdk.java.net/jdk17u-dev/pull/246/files
 Webrev: https://webrevs.openjdk.java.net/?repo=jdk17u-dev&pr=246&range=00
  Issue: https://bugs.openjdk.java.net/browse/JDK-8278766
  Stats: 65 lines in 7 files changed: 45 ins; 6 del; 14 mod
  Patch: https://git.openjdk.java.net/jdk17u-dev/pull/246.diff
  Fetch: git fetch https://git.openjdk.java.net/jdk17u-dev pull/246/head:pull/246

PR: https://git.openjdk.java.net/jdk17u-dev/pull/246