Review request: PR #16491 (fix stale BLOCK_SIZE comments in lucene104)

Hi,

PR #16491 has been open since Aug 6 without a review, and the stale
bot just flagged it, so I'm following its suggestion to notify the
list.

https://github.com/apache/lucene/pull/16491

It's a documentation-only change: BLOCK_SIZE went from 128 to 256 in
10.4, but three comments in Lucene104PostingsWriter/Reader still spell
out values computed with the old block size. It fixes #15670 and
follows up on #15672, where the question was raised whether other
comments needed the same fix.

No behaviour change, no CHANGES.txt entry. Should be a quick review.

Thanks,
Vukasin