[ruby/rdoc] Remove unused abbrev require
This library originally used abbrev to expand abbreviations into fully-qualified classes, but that was replaced in https://github.com/ruby/rdoc/commit/f9ffe6684e2afeac65c62bf1a5a2fce729f21001
abbrev
abbrev is no longer used anywhere, so this commit removes the require.
https://github.com/ruby/rdoc/commit/b76775f27d
Added by dodecadaniel (Daniel Colson) about 3 years ago
[ruby/rdoc] Remove unused abbrev require
This library originally used
abbrevto expand abbreviations intofully-qualified classes, but that was replaced in
https://github.com/ruby/rdoc/commit/f9ffe6684e2afeac65c62bf1a5a2fce729f21001
abbrevis no longer used anywhere, so this commit removes the require.https://github.com/ruby/rdoc/commit/b76775f27d