word_wrap: fix Ruby 2.7 warning
word_wrap: fix Ruby 2.7 warning

This fixes the following warning:

```
vendor/gems/ruby/2.7.0/gems/shoulda-matchers-4.3.0/lib/shoulda/matchers/util/word_wrap.rb:8: 
  warning: Using the last argument as keyword parameters is deprecated; maybe ** should be added to the call
```
biow0lf/shoulda-matchers,thoughtbot/shoulda-matchers,biow0lf/shoulda-matchers,biow0lf/shoulda-matchers,thoughtbot/shoulda-matchers,thoughtbot/shoulda-matchers,biow0lf/shoulda-matchers,thoughtbot/shoulda-matchers