Sync book store

[tomasnorre]

Resolves #842

There are some tests failing, with the example configuration. I had tested with my private implementation too, there some fails too.

So I don't know if some tests aren't meant for the PHP track or what the deal is yet.

I Haven't made as detailed descriptions on the additional tests, they were more confusing than helpful to me.

[github-actions]

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[tomasnorre]

Do you see what's wrong in the logic, that makes the two tests fail?

The linting should get a new release that fixes it within the next week.

[tomasnorre]

Updated to match how I did it in the go-track, in that way it works.

[mk-mxp]

@tomasnorre FYI: I am short of time until December. Please be patient...