Move to Alpine 3.18 and see if it fixes the problems on Windows

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Alpine 3.18 came out literally today and bundles some musl patches to fix DNS over TCP support.

My previous digging pointed those DNS issues as the root cause of #626 on Windows post-Alpine 3.12, so it'd be great if 3.18 fixed everything and allowed me to rip out the windows bandaids.

This'd also give win users proper AVIF/JPEGXL support, which they currently don't have. (see #792)

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Downloading seems to work on 3.18-based Windows version - I need to fix some build pipeline stuff to:

• Make sure we install the previous version of the INotify package (sadly this still ain't fixed with WSL..)
• Remove the dependency on npm for get-version - it used to not be removed on 3.12 builds but that was an error to begin with

[Difegue]

Fixed both of those, things look fine now!