Fix casting issues that trigger NumPy deprecation warnings

[nfahlgren]

Describe your changes In NumPy 1.25, casting single value arrays to Python data types is deprecated. In general this PR extracts the single value before casting to fix the issue (or avoids casting when unnecessary).

Type of update Is this a: cleanup

Associated issues

1566

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• [ ] PR functionality reviewed in a Jupyter Notebook
• [ ] All tests pass
• [ ] Test coverage remains 100%
• [ ] Documentation tested
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• [ ] Code reviewed
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[deepsource-io[bot]]

Here's the code health analysis summary for commits 76cd4a1..e49f15d. View details on DeepSource ↗.

Analysis Summary

Analyzer	Status	Summary	Link
Python	✅ Success		View Check ↗
Test coverage	✅ Success		View Check ↗

Code Coverage Report

Metric	Aggregate	Python
Branch Coverage	100%	100%
Composite Coverage	100%	100%
Line Coverage	100%	100%
New Branch Coverage	100%	100%
New Composite Coverage	100%	100%
New Line Coverage	100%, ✅ Above Threshold	100%, ✅ Above Threshold

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