[skip ci] Update docs for dev env setup per usnistgov/OSCAL#1283.

[aj-stein-nist]

Committer Notes

Some missed bits from #1307. This PR will close #1283 once and for all.

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[aj-stein-nist]

@david-waltermire-nist I am really sorry about this, I didn't circle back on this faster. I was meeting with Arminta. I did set up a clean WSL2 Ubuntu 20.04 installation (and that is more annoying than I thought), and I did notice some docs errors, but the useful bit is we missed the unzip dependency and that is kind of important.

I didn't get to mark it as draft again before you merged, apologies! 😬

[david-waltermire]

LGTM. Thanks!