Update table relation after exchange command

[Somtom]

Related to https://github.com/ClickHouse/dbt-clickhouse/issues/226

Summary

It seems that after running the EXCHANGE TABLES command, the distributed table does not point to the local table anymore (see https://github.com/ClickHouse/dbt-clickhouse/issues/226).

While testing locally, I realized that if we run the create_distributed_table operation once more after the EXCHANGE TABLES, this fixes the problem. Even though I have very few context on dbt adapters, this hopefully helps figuring out the correct solution.

Checklist

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• [ ] Unit and integration tests covering the common scenarios were added
• [ ] A human-readable description of the changes was provided to include in CHANGELOG
• [ ] For significant changes, documentation in https://github.com/ClickHouse/clickhouse-docs was updated with further explanations or tutorials

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[steffen030]

@BentsiLeviav Any chance on getting a review for this PR?

[BentsiLeviav]

Sorry for the delay. I'll do my best to review it within the following days.