Add trailing newline when dumping JSON to files

[janEbert]

Add trailing newline when dumping JSON to files, just to better follow and satisfy POSIX standards. Sorry about the review notifications for such minuscule changes.

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[yobibyte]

Do we need a comment for every line? For me, the actual code is pretty obvious.

[janEbert]

I was considering the same, but since the behavior wasn't followed previously and it doesn't take up additional lines, I thought it would be fine. I'm open to removing the comments, though.