RFR: 8345433: (fs) Use stream to load FileTypeDetectors in Files.probeContentType

[Brian Burkhalter]

Change `FileTypeDetector` list creation to use a stream rather than an iteration and adds.

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Commit messages:
 - 8345433: (fs) Use stream to load FileTypeDetectors in Files.probeContentType

Changes: https://git.openjdk.org/jdk/pull/22552/files
  Webrev: https://webrevs.openjdk.org/?repo=jdk&pr=22552&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8345433
  Stats: 9 lines in 2 files changed: 0 ins; 4 del; 5 mod
  Patch: https://git.openjdk.org/jdk/pull/22552.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/22552/head:pull/22552

PR: https://git.openjdk.org/jdk/pull/22552