RFR: 8335775: Remove extraneous 's' in comment of rawmonitor.cpp test file

[Severin Gehwolf]

Trivial comment only change in a test. Please review!

Thanks!

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Commit messages:
 - 8335775: Remove extraneous 's' in comment of rawmonitor.cpp test file

Changes: https://git.openjdk.org/jdk/pull/20051/files
  Webrev: https://webrevs.openjdk.org/?repo=jdk&pr=20051&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8335775
  Stats: 1 line in 1 file changed: 0 ins; 1 del; 0 mod
  Patch: https://git.openjdk.org/jdk/pull/20051.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/20051/head:pull/20051

PR: https://git.openjdk.org/jdk/pull/20051