Fix: stress error with nscf

[dyzheng]

Reminder

• Have you linked an issue with this pull request?
• Have you added adequate unit tests and/or case tests for your pull request?
• Have you noticed possible changes of behavior below or in the linked issue?
• Have you explained the changes of codes in core modules of ESolver, HSolver, ElecState, Hamilt, Operator or Psi? (ignore if not applicable)

Linked Issue

Fix #6230

Unit Tests and/or Case Tests for my changes

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What's changed?

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Any changes of core modules? (ignore if not applicable)

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