fix cdc redo log storage configuration (#12653)

[ti-chi-bot]

This is an automated cherry-pick of #12653

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What is changed, added or deleted? (Required)

ticdc support use gcs/azure as external storage in redo log.

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• master (the latest development version)
• v6.6 (TiDB 6.6 versions)
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• v6.4 (TiDB 6.4 versions)
• v6.1 (TiDB 6.1 versions) Merge only after release of 6.1.4
• v5.4 (TiDB 5.4 versions)
• v5.3 (TiDB 5.3 versions)
• v5.2 (TiDB 5.2 versions)
• v5.1 (TiDB 5.1 versions)
• v5.0 (TiDB 5.0 versions)

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