fix property value leak in DefaultParser.handleProperties

[rootvector2]

handleProperties calls processValue on the Option registered in Options instead of on the copy that handleOption clones into the CommandLine, so a default applied in one parse() stays on the shared Options and every later parse() on it returns that stale value while an explicit -a two on the command line is pushed into the args list; found while checking why DefaultParser never clears option values the way the legacy Parser does for CLI-71.

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