release-23.2: bump Pebble and split snapshot sstables

[itsbilal]

Backport 1/1 commits from #129018.

/cc @cockroachdb/release

Release justification: Performance improvement that has baked in master for a while, that was originally identified in a support escalation.

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Previously, we'd only create one sstable for all mvcc keys in a range when ingesting a rebalance/recovery snapshot into Pebble. This increased write-amp in Pebble as more sstables would have to be compacted into it (or the sstable then split into smaller ones in Pebble), and had other consequences such as massive filter blocks in the large singular sstable.

This change adds a new cluster setting,
kv.snapshot_rebalance.max_sst_size, that sets the max size of the sstables containing user/mvcc keys in a range. If an sstable exceeds this size in multiSSTWriter, we roll over that sstable and create a new one.

Epic: CRDB-8471
Fixes: #67284

Release note (performance improvement): Reduce the write-amplification impact of rebalances by splitting snapshot sstable files into smaller ones before ingesting them into Pebble.

[blathers-crl]

Thanks for opening a backport.

Please check the backport criteria before merging:

• Backports should only be created for serious
  issues or test-only changes.
• Backports should not break backwards-compatibility.
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  here).
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If your backport adds new functionality, please ensure that the following additional criteria are satisfied:

• There is a high priority need for the functionality that cannot wait until the next release and is difficult to address in another way.
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Also, please add a brief release justification to the body of your PR to justify this
backport.

[cockroach-teamcity]

This change is 

[jbowens]

Reviewed 4 of 4 files at r1, 4 of 4 files at r2, 29 of 29 files at r3, all commit messages.
Reviewable status: complete! 1 of 0 LGTMs obtained (waiting on @aadityasondhi)

[itsbilal]

TFTR!

[itsbilal]

blathers backport 23.2.15-rc

[blathers-crl]

Based on the specified backports for this PR, I applied new labels to the following linked issue(s). Please adjust the labels as needed to match the branches actually affected by the issue(s), including adding any known older branches.

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Issue #67284: branch-release-23.2.15-rc.

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