RFR: 8285523: The test for JDK-8285445 can be improved

[Sergey Bylokhov]

The new test added as part of the [JDK-8285445](https://bugs.openjdk.java.net/browse/JDK-8285445) cannot trigger that bug and pass w/ and w/o fix.

An updated test validates the "default" case when the `jdk.io.File.enableADS` property is not set, in this case the ADS should be [accepted](https://github.com/openjdk/jdk/blob/9d9f4e502f6ddc3116ed9b80f7168a1edfce839e/src/java.base/windows/classes/java/io/WinNTFileSystem.java#L59).

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Commit messages:
 - Initial version of 8285523

Changes: https://git.openjdk.java.net/jdk/pull/8379/files
 Webrev: https://webrevs.openjdk.java.net/?repo=jdk&pr=8379&range=00
  Issue: https://bugs.openjdk.java.net/browse/JDK-8285523
  Stats: 3 lines in 1 file changed: 2 ins; 0 del; 1 mod
  Patch: https://git.openjdk.java.net/jdk/pull/8379.diff
  Fetch: git fetch https://git.openjdk.java.net/jdk pull/8379/head:pull/8379

PR: https://git.openjdk.java.net/jdk/pull/8379