fix(secrets): Skip secrets from files encoded with special codecs

[nimrodkor]

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Description

We got some errors when scanning files with weird, ascii based codecs on non-human-readable files. No need to scan these as it won't help developers not include it in their READABLE files. This skips the file if the codec is bad.

Checklist:

• My code follows the style guidelines of this project
• I have performed a self-review of my own code
• I have commented my code, particularly in hard-to-understand areas
• I have made corresponding changes to the documentation
• I have added tests that prove my feature, policy, or fix is effective and works
• New and existing tests pass locally with my changes
• Any dependent changes have been merged and published in downstream modules