Fix safe_exec

[thinkst-az]

Proposed changes

A recent change restricted the PATH directories where unqualified executables were launched from. This fixes it, and simplifies it's implementation with stdlib's shutil.which.

Types of changes

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• Bugfix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to not work as expected)
• Documentation Update

Checklist

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• I have added tests that prove my fix is effective or that my feature works
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• Linked to the relevant github issue or github discussion