[jdk8u-dev] RFR: 8309138: Fix container tests for jdks with symlinked conf dir

[SendaoYan]

Hi all
This is backport of JDK-8309138, to fix the testcase bug, which if the tested jdk directory is symlinked, symlinks are followed when copying tested jdk.
Only change the testcase lib file, the risk is low.

Additional testing:

- [ ] jdk/test/jdk/internal/platform/docker
- [ ] hotspot/test/runtime/containers/docker

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Commit messages:
 - Backport c1bb926f4d5eaf49777f93b9f8788db243bba83b

Changes: https://git.openjdk.org/jdk8u-dev/pull/538/files
  Webrev: https://webrevs.openjdk.org/?repo=jdk8u-dev&pr=538&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8309138
  Stats: 3 lines in 1 file changed: 2 ins; 0 del; 1 mod
  Patch: https://git.openjdk.org/jdk8u-dev/pull/538.diff
  Fetch: git fetch https://git.openjdk.org/jdk8u-dev.git pull/538/head:pull/538

PR: https://git.openjdk.org/jdk8u-dev/pull/538