cdc: add description about ticdc lightning compatibility

[3AceShowHand]

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For details, see tips for choosing the affected versions (in Chinese).

• master (the latest development version)
• v8.5 (TiDB 8.5 versions)
• v8.4 (TiDB 8.4 versions)
• v8.3 (TiDB 8.3 versions)
• v8.2 (TiDB 8.2 versions)
• v8.1 (TiDB 8.1 versions)
• v7.5 (TiDB 7.5 versions)
• v7.1 (TiDB 7.1 versions)
• v6.5 (TiDB 6.5 versions)
• v6.1 (TiDB 6.1 versions)
• v5.4 (TiDB 5.4 versions)
• v5.3 (TiDB 5.3 versions)

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• Delete files
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[ti-chi-bot]

In response to a cherrypick label: new pull request created to branch release-8.2: #19066.

[ti-chi-bot]

In response to a cherrypick label: new pull request created to branch release-8.3: #19067.

[ti-chi-bot]

In response to a cherrypick label: new pull request created to branch release-8.4: #19068.

[ti-chi-bot]

In response to a cherrypick label: new pull request created to branch release-6.5: #19069.

[ti-chi-bot]

In response to a cherrypick label: new pull request created to branch release-7.1: #19070.