Standardize handling of config files

[NickM-27]

Proposed change

The code to load the config file was duplicated and overall inconsistent. This PR moves the code to the config util to reduce duplicated code and enforce config loading to be consistent.

Type of change

• Dependency upgrade
• Bugfix (non-breaking change which fixes an issue)
• New feature
• Breaking change (fix/feature causing existing functionality to break)
• Code quality improvements to existing code
• Documentation Update

Checklist

• The code change is tested and works locally.
• Local tests pass. Your PR cannot be merged unless tests pass
• There is no commented out code in this PR.
• The code has been formatted using Ruff (ruff format frigate)

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