PARQUET-2064: Make Range public accessible in RowRanges

[shangxinli]

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[gszadovszky]

to should also be final.

[shangxinli]

Fixed it.

[gszadovszky]

I don't like returning ranges directly. This is a mutable list so the caller can modify it without any control. I would suggest wrapping it into an unmodifiable list.

[shangxinli]

Yeah, that makes sense. After this PR, I will change the master branch also.

[gszadovszky]

Oh, just realized this is not on master. Usually, we are doing the other way around. Push to master then backport to other branches. But this way should be fine as well. We do not have too many PRs ongoing.