capitalize "y/n" for clearer intent

[bacongobbler]

First off, thank you for maintaining and making this project publicly available for others! Fist bump 🤜

During the install script process, if you press enter, choice becomes an empty string and will default to "no". The convention in this case is to capitalize the default answer so users know what happens when they auto-accept prompts.

I figured this is such an insignificant change that it doesn't need a note in the CHANGELOG, but please let me know if you'd prefer I add this in.

Thanks! :)

[MagicMirrorBot]

	Warnings
⚠️	Please include an updated CHANGELOG.md file. This way we can keep track of all the contributions.

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