[fix](hudi-mtmv) Fix the issue that Hudi materialized views are not involved in transparent rewriting

[BePPPower]

It's because when Hudi performs transparent rewriting, the timestamp of the base table obtained by loadSnapshot is inconsistent with the timestamp stored after partition refresh, which causes the comparison of tableSnapshot to fail, resulting in the materialized view not being hit.

Currently, the logic of loadSnapshot to obtain the timestamp of the base table is a bit strange and doesn't quite meet expectations. Further in - depth research is needed on how to modify it.

For now, in the getTableSnapshot function, simply return 0L constantly, indicating that the tableSnapshot is always synchronized, to bypass this problem. This modification is consistent with the original expectation of manual refresh. We'll deal with this issue later.

Check List (For Author)

• Test

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  • Manual test (add detailed scripts or steps below)
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• Behavior changed:

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• Does this need documentation?

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[Thearas]

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