/usr/lib/ghc-doc/hoogle/libghc-lambdabot-reference-plugins-doc.txt is in libghc-lambdabot-reference-plugins-doc 5.1.0.1-1build4.
This file is owned by root:root, with mode 0o777.
It is a symlink to /usr/lib/ghc-doc/hoogle/../../../share/doc/libghc-lambdabot-reference-plugins-doc/html/lambdabot-reference-plugins.txt