fix(meta): rename changelog shall check self.from

[xiangjinwu]

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What's changed and what's your intention?

Minor bug since #17132 (v2.0.1)

Refer to the added test. It was blindly changing both a and b into c in the definition of mv 😓

https://buildkite.com/risingwavelabs/pull-request/builds/60608#0192ada6-0ec6-4f20-9272-a53476d3d34c

    query result mismatch:
    [SQL] SELECT definition FROM rw_materialized_views WHERE name = 'mv';
    [Diff] (-expected|+actual)
    -   CREATE MATERIALIZED VIEW mv AS WITH a_log AS changelog from c, b_log AS changelog from b SELECT 'a' AS tbl, * FROM a_log UNION ALL SELECT 'b', * FROM b_log
    +   CREATE MATERIALIZED VIEW mv AS WITH a_log AS changelog from c, b_log AS changelog from c SELECT 'a' AS tbl, * FROM a_log UNION ALL SELECT 'b', * FROM b_log
    at e2e_test/ddl/alter_rename.slt:308

Checklist

• I have written necessary rustdoc comments
• I have added necessary unit tests and integration tests
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Release note

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[xiangjinwu]

Minor test expectation conflict with #19029. Need to wait for it and rebase.