RFR: JDK-8319678: Several tests from corelibs areas ignore VM flags

[Mahendra Chhipa]

Updated following tests to use ProcessTools methods:
 test/jdk/java/lang/Thread/UncaughtExceptionsTest.java
 test/jdk/java/lang/annotation/LoaderLeakTest.java
 test/jdk/java/rmi/reliability/benchmark/bench/rmi/Main.java
 test/jdk/java/time/nontestng/java/time/chrono/HijrahConfigTest.java
 test/jdk/javax/naming/spi/providers/InitialContextTest.java

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Commit messages:
 - JDK-8319678: Several tests from corelibs areas ignore VM flags

Changes: https://git.openjdk.org/jdk/pull/18602/files
  Webrev: https://webrevs.openjdk.org/?repo=jdk&pr=18602&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8319678
  Stats: 138 lines in 5 files changed: 45 ins; 55 del; 38 mod
  Patch: https://git.openjdk.org/jdk/pull/18602.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/18602/head:pull/18602

PR: https://git.openjdk.org/jdk/pull/18602