fix: use original modifiedIndex if possible

[spacewander]

Fix #4160

Signed-off-by: spacewander spacewanderlzx@gmail.com

What this PR does / why we need it:

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• Did you explain what problem does this PR solve? Or what new features have been added?
• Have you added corresponding test cases?
• Have you modified the corresponding document?
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[Yiyiyimu]

I test dozens of times with the reproduce steps from @tzssangglass and also this new test on master branch, and both of them passed without errors. Is there any specific reason to cause this problem, since it seems not always happen.

And if it is triggered randomly, do we need to test it several times to ensure the error would not occur

[spacewander]

@Yiyiyimu
It can be simply reproduced with running my test without my fix.

[Yiyiyimu]

@Yiyiyimu
It can be simply reproduced with running my test without my fix.

Could reproduce for now. Can't find the reason yet maybe there is something configured wrong on my local environment..