RFR: 7903539: Please make jtreg build date reproducible [v2]

[Vladimir Petko]

> This PR is an upstream of the patch by Chris Lamb (lamby at debian.org)[1].
> 
> Testing:
> 
> $ export SOURCE_DATE_EPOCH=1
> $ bash make/build.sh 
> ...
> $ cp build/images/jtreg/lib/jtreg.jar 1.jar
> $ bash make/build.sh 
> ...
> $ strip-nondeterminism build/images/jtreg/lib/jtreg.jar 
> $ strip-nondeterminism 1.jar 
> $ diff 1.jar build/images/jtreg/lib/jtreg.jar 
> $ jar xvf 1.jar
> $ cat META-INF/MANIFEST.MF 
> Manifest-Version: 1.0
> Main-class: com.sun.javatest.regtest.Main
> Class-Path: javatest.jar asmtools.jar
> jtreg-Name: jtreg
> jtreg-VersionString: 7.3.1-dev+0
> jtreg-Version: 7.3.1
> jtreg-Milestone: dev
> jtreg-Build: 0
> jtreg-BuildJavaVersion: Java(TM) 2 SDK, Version 17.0.8+7-Ubuntu-123.04
> jtreg-BuildDate: January 01, 1970
> Created-By: 17.0.8 (Private Build)
> 
> 
> 
> [1] https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=1038957

Vladimir Petko has updated the pull request incrementally with one additional commit since the last revision:

  changelog: Use SOURCE_BUILD_EPOCH to suppport reproducible builds

-------------

Changes:
  - all: https://git.openjdk.org/jtreg/pull/170/files
  - new: https://git.openjdk.org/jtreg/pull/170/files/1a90004c..5f00ee48

Webrevs:
 - full: https://webrevs.openjdk.org/?repo=jtreg&pr=170&range=01
 - incr: https://webrevs.openjdk.org/?repo=jtreg&pr=170&range=00-01

  Stats: 2 lines in 1 file changed: 1 ins; 0 del; 1 mod
  Patch: https://git.openjdk.org/jtreg/pull/170.diff
  Fetch: git fetch https://git.openjdk.org/jtreg.git pull/170/head:pull/170

PR: https://git.openjdk.org/jtreg/pull/170