RFR: 8351086: (fc) Make java/nio/channels/FileChannel/BlockDeviceSize.java test manual

[Brian Burkhalter]

Change `BlockDeviceSize` to be a manual test for the time being.

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Commit messages:
 - 8351086: (fc) Make java/nio/channels/FileChannel/BlockDeviceSize.java test manual

Changes: https://git.openjdk.org/jdk/pull/23877/files
  Webrev: https://webrevs.openjdk.org/?repo=jdk&pr=23877&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8351086
  Stats: 2 lines in 1 file changed: 1 ins; 0 del; 1 mod
  Patch: https://git.openjdk.org/jdk/pull/23877.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/23877/head:pull/23877

PR: https://git.openjdk.org/jdk/pull/23877