release-22.2: kvcoord: disable fatal assertion on transaction commit sanity check

[nvanbenschoten]

Backport 1/1 commits from #107596.

/cc @cockroachdb/release

---

As #103817 is now a known issue for which a root cause has been identified, the sanity check assertion in place here is disabled, with errors occuring due to the known bug properly linking to the issue ticket. While the transaction coordinator still performs sanity checks to ensure that operations cannot continue on an already-committed transaction, it will no longer log the error with severity FATAL, resulting in node crash, and will instead simply return the error.

Part of: #103817

Release note: None

Release justification: Extraordinary fix to mitigate effects of #103817.

[blathers-crl]

Thanks for opening a backport.

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[cockroach-teamcity]

This change is