fix custom hook logic

[jcstorms1]

What does this PR do?

Fixes a small issue with the custom secret key detection hook. Not all files were being scanned before.

Motivation

Testing Guidelines

Additional Notes

Types of Changes

• Bug fix
• New feature
• Breaking change
• Misc (docs, refactoring, dependency upgrade, etc.)

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• This PR contains breaking changes that are documented in the description
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