[jdk25u-dev] RFR: 8365184: sun/tools/jhsdb/HeapDumpTestWithActiveProcess.java Re-enable SerialGC flag on debuggee process

[Roland Mesde]

Backporting JDK-8365184: sun/tools/jhsdb/HeapDumpTestWithActiveProcess.java Re-enable SerialGC flag on debuggee process.

This PR re-enable -XX:+UseSerialGC flag for debuggee process in HeapDumpTestWithActiveProcess.java. The SerialGC was disabled due to classloader-related issue (JDK-8313655), but issue no longer occurs, likely due to improvements in ClassLoaderData handling or SerialGC implementation.

For parity with Oracle JDK.

Ran related tests on linux-x64, linux-aarch64, macos-aarch64 and windows-x64:

make test TEST=test/jdk/sun/tools/jhsdb/JShellHeapDumpTest.java
make test TEST=test/jdk/sun/tools/jhsdb/JShellHeapDumpTest.java JTREG='JAVA_OPTIONS=-XX:+UseSerialGC'

[windows-x64-specific-test.log](https://github.com/user-attachments/files/25078435/windows-x64-specific-test.log)
[windows-x64-specific-2-test.log](https://github.com/user-attachments/files/25078436/windows-x64-specific-2-test.log)
[macos-aarch64-specific-test.log](https://github.com/user-attachments/files/25078437/macos-aarch64-specific-test.log)
[macos-aarch64-specific-2-test.log](https://github.com/user-attachments/files/25078438/macos-aarch64-specific-2-test.log)
[linux-x64-specific-test.log](https://github.com/user-attachments/files/25078439/linux-x64-specific-test.log)
[linux-x64-specific-2-test.log](https://github.com/user-attachments/files/25078440/linux-x64-specific-2-test.log)
[linux-aarch64-specific-test.log](https://github.com/user-attachments/files/25078441/linux-aarch64-specific-test.log)
[linux-aarch64-specific-2-test.log](https://github.com/user-attachments/files/25078442/linux-aarch64-specific-2-test.log)

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Commit messages:
 - Backport 25480f0011297ad209eca1b1b56bcf983ea4ee5d

Changes: https://git.openjdk.org/jdk25u-dev/pull/225/files
  Webrev: https://webrevs.openjdk.org/?repo=jdk25u-dev&pr=225&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8365184
  Stats: 6 lines in 1 file changed: 0 ins; 5 del; 1 mod
  Patch: https://git.openjdk.org/jdk25u-dev/pull/225.diff
  Fetch: git fetch https://git.openjdk.org/jdk25u-dev.git pull/225/head:pull/225

PR: https://git.openjdk.org/jdk25u-dev/pull/225