[jdk8u-dev] RFR: 8340660: [8u] Test com/sun/jdi/PrivateTransportTest.sh fails on MacOS

[Zdenek Zambersky]

Turns out there is still one failing jdi test on MacOS (after DNS issue with macos-13 image was fixed):
`com/sun/jdi/PrivateTransportTest.sh`

**Error:**

STDOUT:
JDK under test is: /Users/runner/jdk-macos-x64/jdk-1.8.0-internal+0_osx-x64_bin/j2sdk-image
Setup private transport library by copying an existing one and renaming
cp /Users/runner/jdk-macos-x64/jdk-1.8.0-internal+0_osx-x64_bin/j2sdk-image/jre/lib/libdt_socket.dylib /Users/runner/work/jdk8u-dev/jdk8u-dev/test-results/testoutput/jdk_tier1/JTwork/classes/com/sun/jdi/libprivate_dt_socket.dylib
LD_LIBRARY_PATH=/Users/runner/work/jdk8u-dev/jdk8u-dev/test-results/testoutput/jdk_tier1/JTwork/classes/com/sun/jdi
/Users/runner/jdk-macos-x64/jdk-1.8.0-internal+0_osx-x64_bin/j2sdk-image/bin/java -agentlib:jdwp=transport=private_dt_socket,server=y,suspend=n -classpath "/Users/runner/work/jdk8u-dev/jdk8u-dev/test-results/testoutput/jdk_tier1/JTwork/classes/com/sun/jdi" HelloWorld
FATAL ERROR in native method: JDWP No transports initialized, jvmtiError=AGENT_ERROR_TRANSPORT_LOAD(196)
test status for  was: 134
The test failed :-(
exit status was 134
STDERR:
ERROR: transport library not found: private_dt_socket
ERROR: JDWP Transport private_dt_socket failed to initialize, TRANSPORT_LOAD(509)
JDWP exit error AGENT_ERROR_TRANSPORT_LOAD(196): No transports initialized [debugInit.c:750]
/Users/runner/work/jdk8u-dev/jdk8u-dev/jdk/test/com/sun/jdi/PrivateTransportTest.sh: line 203: 16866 Abort trap: 6           /Users/runner/jdk-macos-x64/jdk-1.8.0-internal+0_osx-x64_bin/j2sdk-image/bin/java -agentlib:jdwp=transport=private_dt_socket,server=y,suspend=n -classpath "/Users/runner/work/jdk8u-dev/jdk8u-dev/test-results/testoutput/jdk_tier1/JTwork/classes/com/sun/jdi" HelloWorld
unspecified test failure


**Details:**
Test fails to load native library. Issue is, that `LD_LIBRARY_PATH` env. var is [no longer supported by newer versions MacOS](https://forums.developer.apple.com/forums/thread/705308). Fix is to use `DYLD_LIBRARY_PATH` env. var instead. Fix is specific to 8u, because jdi tests were rewritten to java in later JDKs in [series of changes](https://bugs.openjdk.org/browse/JDK-8201652). I believe, in rewritten test , issue was then fixed as part of [JDK-8216265](https://bugs.openjdk.org/browse/JDK-8216265). Backporting all of that just to fix this, seems like overkill, so I made fix to shell test.

**Testing:**
Tier1: OK

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

Commit messages:
 - PrivateTransportTest.sh: fix library problem on macos

Changes: https://git.openjdk.org/jdk8u-dev/pull/580/files
  Webrev: https://webrevs.openjdk.org/?repo=jdk8u-dev&pr=580&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8340660
  Stats: 5 lines in 1 file changed: 0 ins; 0 del; 5 mod
  Patch: https://git.openjdk.org/jdk8u-dev/pull/580.diff
  Fetch: git fetch https://git.openjdk.org/jdk8u-dev.git pull/580/head:pull/580

PR: https://git.openjdk.org/jdk8u-dev/pull/580