Fix coordinate in README

[RickMoynihan]

I did create a small patch to the README for this, but then figured it would be better to make an issue for it as there are probably better fixes.

Basically this tools.deps coordinate is wrong:

io.github.juxt/pack {:git/sha "1a077d172afc94e7f7679ecaad57ed9b7dde687d"}

It errors with

Cloning: https://github.com/juxt/pack.git
Error building classpath. Unable to clone /Users/rick/.gitlibs/_repos/https/github.com/juxt/pack
fatal: could not read Username for 'https://github.com': terminal prompts disabled

And changing it to this works:

io.github.juxt/pack.alpha {:git/sha "1a077d172afc94e7f7679ecaad57ed9b7dde687d"}

However I think a better fix is probably just to rename the repository in github to pack; as the API namespaces are now no longer packaged under .alpha; I can only assume this is the intent. Obviously I can't submit a PR for that renames the repo though :-)

Thanks again 🙇

[SevereOverfl0w]

I really want to rename the repo, and I think we should. I've created the Stable milestone to mark out any outstanding tasks that need tackling first. There's nothing scary there.