jmx-dev RFR: 8346261: Cleanup in JDP tests

[Kevin Walls]

Simple test update to fix some typos and formatting changes, seen while investigating and testing for JDK-8241865.

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Commit messages:
 - 8346261: Cleanup in JDP tests

Changes: https://git.openjdk.org/jdk/pull/22761/files
  Webrev: https://webrevs.openjdk.org/?repo=jdk&pr=22761&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8346261
  Stats: 37 lines in 10 files changed: 5 ins; 7 del; 25 mod
  Patch: https://git.openjdk.org/jdk/pull/22761.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/22761/head:pull/22761

PR: https://git.openjdk.org/jdk/pull/22761