[CICD] TEST ONLY: decrease cpu cores for py tests

[YanxuanLiu]

Fixes # .

Description

A few sentences describing the changes proposed in this pull request.

Status

Ready/Work in progress/Hold

Types of changes

• [x] Non-breaking change (fix or new feature that would not break existing functionality).
• [ ] Breaking change (fix or new feature that would cause existing functionality to change).
• [ ] New tests added to cover the changes.
• [ ] Integration tests passed locally by running ./runtests.sh -f -u --net --coverage.
• [ ] Quick tests passed locally by running ./runtests.sh --quick --unittests --disttests.
• [ ] In-line docstrings updated.
• [ ] Documentation updated, tested make html command in the docs/ folder.

[YanxuanLiu]

/build

[YanxuanLiu]

/build

[YanxuanLiu]

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[YanxuanLiu]

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[YanxuanLiu]

/build

[YanxuanLiu]

/build

[YanxuanLiu]

/build

[YanxuanLiu]

/build

[YanxuanLiu]

/build

[YanxuanLiu]

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[YanxuanLiu]

/build

[wyli]

thanks, the recent runs are pretty fast and stable now, closing this.