[jdk11u-dev] RFR: 8259268: Refactor InheritIO shell test as java test

[SendaoYan]

Hi all,

This pull request contains a backport of commit [fb46d4e5](https://github.com/openjdk/jdk/commit/fb46d4e578db297c66176852bec77fc3ad5b89a8) from the [openjdk/jdk](https://git.openjdk.org/jdk) repository.

The commit being backported was authored by Ivan Šipka on 6 Feb 2021 and was reviewed by Igor Ignatyev and Roger Riggs.

Thanks!

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Commit messages:
 - Backport fb46d4e578db297c66176852bec77fc3ad5b89a8

Changes: https://git.openjdk.org/jdk11u-dev/pull/3006/files
  Webrev: https://webrevs.openjdk.org/?repo=jdk11u-dev&pr=3006&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8259268
  Stats: 215 lines in 3 files changed: 84 ins; 131 del; 0 mod
  Patch: https://git.openjdk.org/jdk11u-dev/pull/3006.diff
  Fetch: git fetch https://git.openjdk.org/jdk11u-dev.git pull/3006/head:pull/3006

PR: https://git.openjdk.org/jdk11u-dev/pull/3006