[jdk11u-dev] RFR: 8217527: jmod hash does not work if --hash-module does not include the target module

[Daniel Hu]

I'd like to backport this fix because currently `jmod hash` command does not work on already created modules and this fixes that issue. This isn't intended behavior; nothing in Oracle documentation states this limitation, and moreover the command itself gives opaque response: there's no error message or non-zero exit, instead the command does nothing and no modules are changed after hashing.

The backport isn't clean because of conflicts in `HashesTest.java`. The conflicts are due to later backports having affected the test first; resolution was simple as all the current code was kept. This change was ran on internal Amazon pipelines and passes jtreg tier1-4 + tck tests on all platforms: linux x64, aarch64, x86, arm32; macos x64, arrch64; windows x64, x86.

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Commit messages:
 - Backport 35554ea08557d73637bdb141935b7c081da7742b

Changes: https://git.openjdk.org/jdk11u-dev/pull/3039/files
  Webrev: https://webrevs.openjdk.org/?repo=jdk11u-dev&pr=3039&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8217527
  Stats: 100 lines in 4 files changed: 71 ins; 13 del; 16 mod
  Patch: https://git.openjdk.org/jdk11u-dev/pull/3039.diff
  Fetch: git fetch https://git.openjdk.org/jdk11u-dev.git pull/3039/head:pull/3039

PR: https://git.openjdk.org/jdk11u-dev/pull/3039