RFR: 7904126: PrintWriter(s) used by jtreg for agent logging aren't using autoFlush

[Jaikiran Pai]

Can I please get a review of this change which addresses the issue noted in https://bugs.openjdk.org/browse/CODETOOLS-7904126? 

With this change the logs written out to agent.trace and agentServer.<id>.trace should now have these log message more promptly written out and thus help debug and unexpected test failures. Furthermore, the explicit flush() that was done in https://bugs.openjdk.org/browse/CODETOOLS-7903470 has now been replaced with the use of this autoFlush=true to avoid having to explicitly flush() at any call sites where the logger is used to write out the logs.

Given the nature of the change no new self tests have been introduced.

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Commit messages:
 - 7904126: PrintWriter(s) used by jtreg for agent logging aren't using autoFlush

Changes: https://git.openjdk.org/jtreg/pull/305/files
  Webrev: https://webrevs.openjdk.org/?repo=jtreg&pr=305&range=00
  Issue: https://bugs.openjdk.org/browse/CODETOOLS-7904126
  Stats: 6 lines in 2 files changed: 0 ins; 1 del; 5 mod
  Patch: https://git.openjdk.org/jtreg/pull/305.diff
  Fetch: git fetch https://git.openjdk.org/jtreg.git pull/305/head:pull/305

PR: https://git.openjdk.org/jtreg/pull/305