RFR: 8253620: Debug symbols for tests missing on macos and windows

[Erik Joelsson]

Tests on Linux (and I assume other unix like OSes) are built with debug enabled and debug symbols internal. On Windows and macos, internal debug symbols aren't possible, and we have for some reason hard coded not including the external debug symbols in the test-image. In this patch I'm changing this so that we include debug symbols in the easiest possible way on all three platforms.

This patch also invalidates [JDK-8311545](https://bugs.openjdk.org/browse/JDK-8311545) since we now include debug symbols for all test libs and executables.

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Commit messages:
 - JDK-8253620

Changes: https://git.openjdk.org/jdk/pull/15574/files
 Webrev: https://webrevs.openjdk.org/?repo=jdk&pr=15574&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8253620
  Stats: 11 lines in 2 files changed: 9 ins; 1 del; 1 mod
  Patch: https://git.openjdk.org/jdk/pull/15574.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/15574/head:pull/15574

PR: https://git.openjdk.org/jdk/pull/15574