bundle exec standardrb --fix

```
standard: Use Ruby Standard Style (https://github.com/standardrb/standard)
  Rakefile:34:34: Style/RedundantParentheses: Don't use parentheses around a logical expression.
  lib/factory_bot/attribute_assigner.rb:16:32: Performance/StringIdentifierArgument: Use `:"#{attribute}="` instead of `"#{attribute}="`.
standard: Run `standardrb --fix` to fix up to 2 problems.
```

Author: ydah

Rakefile

@@ -31,7 +31,7 @@ task spec: ["spec:unit", "spec:acceptance"]
 
 Cucumber::Rake::Task.new(:features) do |t|
   t.fork = true
-  t.cucumber_opts = ["--format", (ENV["CUCUMBER_FORMAT"] || "progress")]
+  t.cucumber_opts = ["--format", ENV["CUCUMBER_FORMAT"] || "progress"]
 end
 
 YARD::Rake::YardocTask.new do |t|

lib/factory_bot/attribute_assigner.rb

@@ -13,7 +13,7 @@ def object
       @evaluator.instance = build_class_instance
       build_class_instance.tap do |instance|
         attributes_to_set_on_instance.each do |attribute|
-          instance.public_send("#{attribute}=", get(attribute))
+          instance.public_send(:"#{attribute}=", get(attribute))
           @attribute_names_assigned << attribute
         end
       end