chore: add more comments for auto compact and remove the settings table goldenfile test

[BohuTANG]

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Summary

• add more comments for fuse compact
• refine the desciption for auto_compaction_threshold setting
• remove test_settings_table unit test, this is not useful, we need to generate it again and again if we modify the settings, waste time :)

Fixes #[Link the issue here]

Tests

• Unit Test
• Logic Test
• Benchmark Test
• No Test - Existing tests cover.

Type of change

• Bug Fix (non-breaking change which fixes an issue)
• New Feature (non-breaking change which adds functionality)
• Breaking Change (fix or feature that could cause existing functionality not to work as expected)
• Documentation Update
• Refactoring
• Performance Improvement
• Other (please describe):

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This change is 

[BohuTANG]

Dev / linux / sqllogic / cluster (base, mysql) (pull_request) is not related to this PR, it's a flaky test.