Enhancement: Rails/Pluck to support strings / literals?

[vlad-pisanov]

Currently, Rails/Pluck only detects symbol keys, such as:

[ { a: 42 }].map { |x| x[:a] }
# cop recommends [ { a: 42 }].pluck(:a) 

but not String keys:

[ { 'a' => 42 }].map { |x| x['a'] }
# cop ignores

pluck() supports both Symbols and Strings, so it seems like this cop should work on both datatypes. It might actually work for any literal:

[ { false => 42 } ].pluck(false)
# => [42]