Fixed invalid check for current LogLevel in ProcessException message.

[alphaleonis]

Logger was deprecated some time ago, and it seems that the Logger.LogLevel property is always LogLevel.Normal now.
This broke the formatting of exception messages for ProcessException so that they no longer included the tool output if verbosity was set to Verbose (or Trace). The correct place to check current log level seems to be Logging.Level. Updated the message formatting in ProcessException to fix this.

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