Add -Wunused-packages to the packages (#9663)

* Add -Wunused-packages to the packages

Cabal, Cabal-syntax, cabal-install, cabal-install-solver

* Remove unused text dependency

* remove unguarded warning

* Remove 8.10 condition for unused-packages

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Co-authored-by: mergify[bot] <37929162+mergify[bot]@users.noreply.github.com>