Backport #11266: Add GHC Unit ID store to cabal path output

[mergify]

This addds the GHC Project Unit ID store path to the cabal path output as "project-unit-id". The GHC "Project Unit ID" store path has been used in cabal-install since 3.12.1.0.

Example output:

compiler-flavour: ghc
compiler-id: ghc-9.10.1
compiler-path: /nix/store/367sp8xqvk70a050fm6f8a93lig0gx41-ghc-9.10.1/bin/ghc
compiler-store-path: /home/sgillespie/.local/state/cabal/store/ghc-9.10.1-be9a
cache-home: /home/sgillespie/.cache/cabal
remote-repo-cache: /home/sgillespie/.cache/cabal/packages
logs-dir: /home/sgillespie/.cache/cabal/logs
store-dir: /home/sgillespie/.local/state/cabal/store
config-file: /home/sgillespie/.config/cabal/config
installdir: /home/sgillespie/.local/bin

Note that the new value is "project-unit-id", although I'm not 100% this makes sense. Let me know if there's a better name.

EDIT: Changed name to "compiler-store-path"

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  This is an automatic backport of pull request Add GHC Unit ID store to cabal path output #11266 done by Mergify.