Nbb support

[ikappaki]

Add support for nbb including test, addresses #641

HI @borkdude, I've provisionally added nbb in the intrerpreter-mode-alist as something that could appear in the shebang so that clojure mode can pick the script as cljs file, but couldn't find any example using this. Is this a valid case?

Thanks

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Thanks!

[ikappaki]

I've noticed that emacs-28 was missing from the CI and I took the opportunity to add it, let me know if you would like me to revert.

Btw, whya are the circleci failing on master? some auth key might have expired? Thanks

[borkdude]

It might be a valid use case, but I haven't seen it a lot either.

[bbatsov]

Btw, whya are the circleci failing on master? some auth key might have expired? Thanks

I thought I had fixed this already.

[bbatsov]

Thanks!