RFR: 8316452: java/lang/instrument/modules/AppendToClassPathModuleTest.java ignores VM flags

[Leonid Mesnik]

The test uses specific classpath, and jar and is intended to test modules. So I marked is as flagless,

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Commit messages:
 - 8316452

Changes: https://git.openjdk.org/jdk/pull/16080/files
 Webrev: https://webrevs.openjdk.org/?repo=jdk&pr=16080&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8316452
  Stats: 1 line in 1 file changed: 1 ins; 0 del; 0 mod
  Patch: https://git.openjdk.org/jdk/pull/16080.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/16080/head:pull/16080

PR: https://git.openjdk.org/jdk/pull/16080