Give asum, msum, and Product instances explicit kind signatures
#611
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This adds more explicit `Type -> Type` kind signatures to definitions that would otherwise be kind-generalized to have overly polymorphic kinds: * The kinds of `Asum` and `Msum` (the promoted counterparts to the term-level `asum` and `msum` functions, respectively). * The helper type families generated when promoting the `Alternative` and `MonadPlus` instances for `Data.Functor.Product`. This sort of kind polymorphism isn't observable by users in today's GHC, but it will cause problems later in a future version of GHC that implements [GHC#23515](https://gitlab.haskell.org/ghc/ghc/-/issues/23515). (See #601.) (I should have added these as part of #606 or #607, but I forgot them due to an oversight.)
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This adds more explicit
Type -> Typekind signatures to definitions that would otherwise be kind-generalized to have overly polymorphic kinds:AsumandMsum(the promoted counterparts to the term-levelasumandmsumfunctions, respectively).AlternativeandMonadPlusinstances forData.Functor.Product. This sort of kind polymorphism isn't observable by users in today's GHC, but it will cause problems later in a future version of GHC that implements GHC#23515. (See Makesingletonsbuildable after GHC#23515 #601.)(I should have added these as part of #606 or #607, but I forgot them due to an oversight.)