[jdk15u-dev] RFR: 8287463: JFR: Disable TestDevNull.java on Windows

[Ekaterina Vergizova]

I'd like to backport JDK-8287463 to 15u.
This test-only fix disables jdk/jfr/api/recording/dump/TestDumpDevNull.java test on Windows.
Without this fix the test fails with "java.nio.file.NoSuchFileException: \dev\null".
The test is added by JDK-8282947 which is already backported to 15u.
The patch applies cleanly.

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Commit messages:
 - Backport 0df4748216ab71937cfcfb86a2d66f3568bced1e

Changes: https://git.openjdk.org/jdk15u-dev/pull/264/files
 Webrev: https://webrevs.openjdk.org/?repo=jdk15u-dev&pr=264&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8287463
  Stats: 2 lines in 1 file changed: 0 ins; 1 del; 1 mod
  Patch: https://git.openjdk.org/jdk15u-dev/pull/264.diff
  Fetch: git fetch https://git.openjdk.org/jdk15u-dev pull/264/head:pull/264

PR: https://git.openjdk.org/jdk15u-dev/pull/264