refactor: remove substrait ser/de for region query in standalone

[MichaelScofield]

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What's changed and what's your intention?

close #3520

This PR makes the logical plan in region query request not always be serialized to and deserialized from substrait bytes, which is not necessary in standalone mode.

Checklist

• [ ] I have written the necessary rustdoc comments.
• [ ] I have added the necessary unit tests and integration tests.
• [x] This PR does not require documentation updates.