release-23.1: storage: fix PebbleFileRegistry bug that drops entry on rollover

[blathers-crl]

Backport 1/1 commits from #107249 on behalf of @sumeerbhola.

/cc @cockroachdb/release

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The writeToRegistryFile method first writes the new batch, containing file mappings, to the registry file, and then if the registry file is too big, creates a new registry file. The new registry file is populated with the contents of the map, which doesn't yet contain the edits in the batch, resulting in a loss of these edits when the file registry is reopened. This PR changes the logic to first rollover if the registry file is too big, and then writes the batch to the new file.

This bug has existed since the record writer based registry was implemented 239377a. When it leads to a loss of a file mapping in the registry, it will be noticed by Pebble as a corruption (so not a silent failure) since the file corresponding to the mapping will be assumed to be unencrypted, but can't be successfully read as an unencrypted file. Since we have not seen this occur in production settings, we suspect that an observable mapping loss is rare because compactions typically rewrite the files in those lost mappings before the file registry is reopened.

Epic: none

Fixes: #106617

Release note: None

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Release justification: fix for (non-silent) data corruption bug that causes node failure

[blathers-crl]

Thanks for opening a backport.

Please check the backport criteria before merging:

• Patches should only be created for serious issues or test-only changes.
• Patches should not break backwards-compatibility.
• Patches should change as little code as possible.
• Patches should not change on-disk formats or node communication protocols.
• Patches should not add new functionality.
• Patches must not add, edit, or otherwise modify cluster versions; or add version gates.

If some of the basic criteria cannot be satisfied, ensure that the exceptional criteria are satisfied within.

• There is a high priority need for the functionality that cannot wait until the next release and is difficult to address in another way.
• The new functionality is additive-only and only runs for clusters which have specifically “opted in” to it (e.g. by a cluster setting).
• New code is protected by a conditional check that is trivial to verify and ensures that it only runs for opt-in clusters.
• The PM and TL on the team that owns the changed code have signed off that the change obeys the above rules.

Add a brief release justification to the body of your PR to justify this backport.

Some other things to consider:

• What did we do to ensure that a user that doesn’t know & care about this backport, has no idea that it happened?
• Will this work in a cluster of mixed patch versions? Did we test that?
• If a user upgrades a patch version, uses this feature, and then downgrades, what happens?

[cockroach-teamcity]

This change is 

[jbowens]

lgtm

[sumeerbhola]

TFTR!