[SUREFIRE-2135] Use native.encoding for parsing ps

[andpab]

• Use the value of the system property native.encoding as charset for parsing the output of the ps command that ForkedBooter issues on Unix-like OSes when checking if the forked process is still alive
• Fall back to UTF-8 in case the system property is absent (pre-JDK17)
• Remove an unnecessary System.out.println in a test that was probably committed by accident

This fixes the ConsoleOutputIT on Java 18 and above.

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[slawekjaranowski]

@andpab thanks 👏

[andpab]

Amended the commit as suggested by @michael-o

New commit message is:

- Use the value of the system property native.encoding as charset for
  parsing the output of the ps command that ForkedBooter issues on
  Unix-like OSes when checking if the forked process is still alive
- Fall back to file.encoding if native.encoding is absent (pre-JDK17)
- Fall back further to UTF-8 if file.encoding is not explicitly given
- Remove an unnecessary System.out.println in a test that was probably
  committed by accident

This fixes the ConsoleOutputIT on Java 18 and above.

[slawekjaranowski]

issue number should be in square brackets in commit subject, I can change it during merging 😄

[andpab]

I've amended the commit to add the brackets to the issue reference in the commit message.

[michael-o]

LGTM.