Fix Haddock docs for Distribution.Types.Dependency (#10197)

Type `Dependency` is an instance of `Ord`, from `Cabal-syntax-3.10.1.0`.

Co-authored-by: mergify[bot] <37929162+mergify[bot]@users.noreply.github.com>
(cherry picked from commit 33bd14c)

Cabal-syntax/src/Distribution/Types/Dependency.hs

@@ -33,10 +33,6 @@ import qualified Text.PrettyPrint as PP
 --
 -- /Invariant:/ package name does not appear as 'LSubLibName' in
 -- set of library names.
---
--- /Note:/ 'Dependency' is not an instance of 'Ord', and so it cannot be used
--- in 'Set' or as the key to a 'Map'.  For these and similar use cases see
--- 'DependencyMap'.
 data Dependency
   = -- | The set of libraries required from the package.
     -- Only the selected libraries will be built.