PR #90872 - sql: add implicit_txn column to insights execution

[cockroach-teamcity]

Exalate commented:

Related PR: cockroachdb/cockroach#90872
Commit: cockroachdb/cockroach@e2cc21c

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Release note (sql change): Adds a new column implicit_txn
(boolean) to crdb_internal.cluster_execution_insights and
crdb_internal.node_execution_insights

Jira Issue: DOC-6081