fix: Add shebang to fixup scripts

[colincadams]

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Fixes #48 🦕

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[colincadams]

@googlebot I signed it!

[averikitsch]

@busunkim96 the error is: This project needs at least Sphinx v1.6.3 and therefore cannot be built with this version. This is blocking the other PRs as well.

[busunkim96]

@averikitsch It looks like the templates in this library were a bit old. I regenerated manually in #34 which also fixed the shebang issue.

[colincadams]

Thanks for fixing this!