fix: fix cuda initialization error in experiment grid

[Gaiejj]

Description

Modify the multi-process context to default fork to spawn.

Motivation and Context

close #314

• [x] I have raised an issue to propose this change (required for new features and bug fixes)

Types of changes

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• [x] Bug fix (non-breaking change which fixes an issue)
• [ ] New feature (non-breaking change which adds core functionality)
• [ ] Breaking change (fix or feature that would cause existing functionality to change)
• [ ] Documentation (update in the documentation)

Checklist

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• [x] I have read the CONTRIBUTION guide. (required)
• [ ] My change requires a change to the documentation.
• [x] I have updated the tests accordingly. (required for a bug fix or a new feature)
• [ ] I have updated the documentation accordingly.
• [x] I have reformatted the code using make format. (required)
• [x] I have checked the code using make lint. (required)
• [x] I have ensured make test pass. (required)

[codecov[bot]]

Codecov Report

All modified and coverable lines are covered by tests :white_check_mark:

Project coverage is 96.57%. Comparing base (efe7d9c) to head (a88325e).

Additional details and impacted files

```diff @@ Coverage Diff @@ ## main #315 +/- ## ========================================== + Coverage 96.56% 96.57% +0.01% ========================================== Files 139 139 Lines 7089 7090 +1 ========================================== + Hits 6845 6847 +2 + Misses 244 243 -1 ```

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