Insufficient changelog for haddock-library-1.11.0

[andreasabel]

https://hackage.haskell.org/package/haddock-library-1.11.0/changelog merely says:

Add support for linking identifiers with a quote between backticks (#1408)

However, there have been API changes as well: E.g. markupOrderedList has type:

• [a] -> a in 1.10.0: https://hackage.haskell.org/package/haddock-library-1.10.0/docs/Documentation-Haddock-Types.html#t:DocMarkupH
• [(Int, a)] -> a in 1.11.0: https://hackage.haskell.org/package/haddock-library-1.11.0/docs/Documentation-Haddock-Types.html#t:DocMarkupH

In the wild:

• Build error of current master caused by haddock-library-1.11.0 hackage-server#1128

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