RFR: 8355444: [java.io] Use @requires tag instead of exiting based on "os.name" property value [v6]

[Brian Burkhalter]

> Use the `@requires` tag instead of obtaining the operating system name from the `os.name` property and then exiting if the test is not run on that operating system.

Brian Burkhalter has updated the pull request incrementally with one additional commit since the last revision:

  8355444: Remove requires tag from ManyFiles

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Changes:
  - all: https://git.openjdk.org/jdk/pull/24860/files
  - new: https://git.openjdk.org/jdk/pull/24860/files/4cee3c2b..260cb693

Webrevs:
 - full: https://webrevs.openjdk.org/?repo=jdk&pr=24860&range=05
 - incr: https://webrevs.openjdk.org/?repo=jdk&pr=24860&range=04-05

  Stats: 2 lines in 1 file changed: 0 ins; 2 del; 0 mod
  Patch: https://git.openjdk.org/jdk/pull/24860.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/24860/head:pull/24860

PR: https://git.openjdk.org/jdk/pull/24860