RFR: 8294519: (fs) java/nio/file/Files/CopyProcFile.java fails intermittenly due to unstable /proc/cpuinfo output

[Brian Burkhalter]

1. Change source from `/proc/cpuinfo` to `/proc/version`.
2. Do not swallow errors in `@BeforeTest` config action.
3. Remove test from problem list.

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Commit messages:
 - 8294519: (fs) java/nio/file/Files/CopyProcFile.java fails intermittenly due to unstable /proc/cpuinfo output

Changes: https://git.openjdk.org/jdk/pull/10479/files
 Webrev: https://webrevs.openjdk.org/?repo=jdk&pr=10479&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8294519
  Stats: 13 lines in 2 files changed: 3 ins; 6 del; 4 mod
  Patch: https://git.openjdk.org/jdk/pull/10479.diff
  Fetch: git fetch https://git.openjdk.org/jdk pull/10479/head:pull/10479

PR: https://git.openjdk.org/jdk/pull/10479