feat: Implement Modify Table Connection

[Xuanwo]

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Summary

This PR adds the support for Modify Table Connection.

One uncommon but possible scenario is that users may want to update the connection settings for an external table. For instance, their AK/SK credentials might need to be rotated, or the role_arn could change. This PR adds support for such updates.

CREATE OR REPLACE TABLE external_table_test (
    id INTEGER,
    name VARCHAR,
    age INT
) 
's3://testbucket/13_fuse_external_table/' 
CONNECTION=(connection_name = 'external_table_conn');

ALTER TABLE external_table_test CONNECTION=( connection_name = 'external_table_conn_new' );

Only credential-related settings such as access_key_id or secret_access_key can be changed. Any changes to bucket, region, or root will be safely ignored.

Tests

• Unit Test
• Logic Test
• Benchmark Test
• No Test - Explain why

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