--eval-store breaks remote building

[Ericson2314]

Describe the bug

The problem is that the build hook tries to read the derivation from the default store (the one with the url in settings.storeUri). It has no idea about worker.evalStore.

The solution is to get rid of the build hook #5025. Then we don't have to worry about transporting information from local variables to another process, and doing the right thing will be easy.

Steps To Reproduce

nix-build -I nixpkgs=channel:nixpkgs-unstable '<nixpkgs>' -A hello --eval-store $PWD/foo --max-jobs 0 --no-substitute --store $PWD/bar --builders auto

The will fail with ....drv' is not a valid store path, when the build hook attempt to read in the derivation

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