PR #107044 - sql: add a retry loop for stmts in READ COMMITTED txns

[cockroach-teamcity]

Exalate commented:

Related PR: cockroachdb/cockroach#107044
Commit: cockroachdb/cockroach@7f8f436
Fixes: CRDB-26568

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Release note (sql change): Added the
max_retries_for_read_committed session variable. It
defaults to 10, and determines the number of times an individual
statement in an explicit READ COMMITTED transaction will be retried
if it encounters a retriable transaction error.

Jira Issue: DOC-8600