Dynamic Table testing improvements

[mikealfare]

Problem

Dynamic table testing takes a long time to run and is difficult to add to. We need to add Iceberg table format support and updating the tests would make it easier to add to.

Solution

Update the tests separately in this PR and then rebase the existing Snowflake PR on this one.

Checklist

• [x] I have read the contributing guide and understand what's expected of me
• [x] I have run this code in development and it appears to resolve the stated issue
• [x] This PR includes tests, or tests are not required/relevant for this PR
• [x] This PR has no interface changes (e.g. macros, cli, logs, json artifacts, config files, adapter interface, etc) or this PR has already received feedback and approval from Product or DX

[github-actions[bot]]

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