Make Logger safe from static initialization order fiasco (NGWPC-7168)

[PhilMiller]

In dynamic initialization of a global static instance of InterpreterUtil, there was a call to LOG that happened to be running before the dynamic initialization of the class-static members of Logger. This led to invalid memory accesses and hence crashes. These crashes were a symptom of C++ Static Initialization Order Fiasco.

Changes

• Logger: Make most member variables instance members rather than static, and introduce a GetLogger() function to contain a static pointer to a simple singleton instance that can be initialized safely

Testing

1. CI Pipeline
2. Private modification of test_bmi_python to trigger the failure case regardless of a NumPy version mismatch

Checklist

• PR has an informative and human-readable title
• Changes are limited to a single goal (no scope creep)
• Code can be automatically merged (no conflicts)
• Code follows project standards (link if applicable)
• Passes all existing automated tests
• Any change in functionality is tested
• New functions are documented (with a description, list of inputs, and expected output)
• Placeholder code is flagged / future todos are captured in comments
• Project documentation has been updated (including the "Unreleased" section of the CHANGELOG)
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