Fix typo in Release.get_code_paths/1

[aaronrenner]

Summary of changes

Fixing a misspelling in the docs for Release.get_code_paths/1.

Checklist

• New functions have typespecs, changed functions were updated
• Same for documentation, including moduledocs
• Tests were added or updated to cover changes
• Commits were squashed into a single coherent commit

Licensing/Copyright

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related material intended to be compiled or integrated with the source code for Distillery
(the "Contribution"). My Contribution is licensed under the MIT License.