`FactoryBot/AssociationStyle` autocorrection is wrong when the trait is not a symbol literal

[r7kamura]

Ideally, I expect the following to be autocorrection:

# bad
association :user, foo

# good
user factory: [:user, foo]

However, when the trait is such a non-symbol-literal, the autocorrection unintentionally removes it like this:

# autocorrection result
user

This behavior can be confirmed by the following test case:

diff --git a/spec/rubocop/cop/factory_bot/association_style_spec.rb b/spec/rubocop/cop/factory_bot/association_style_spec.rb
index 01afc88..fbe0bab 100644
--- a/spec/rubocop/cop/factory_bot/association_style_spec.rb
+++ b/spec/rubocop/cop/factory_bot/association_style_spec.rb
@@ -113,6 +113,23 @@ RSpec.describe RuboCop::Cop::FactoryBot::AssociationStyle do
       end
     end
 
+    context 'when `association` is called with non-symbol trait' do
+      it 'registers and corrects an offense' do
+        expect_offense(<<~RUBY)
+          factory :article do
+            association :user, foo
+            ^^^^^^^^^^^^^^^^^^^^^^ Use implicit style to define associations.
+          end
+        RUBY
+
+        expect_correction(<<~RUBY)
+          factory :article do
+            user factory: [:user, foo]
+          end
+        RUBY
+      end
+    end
+
     context 'when `association` is called with factory option' do
       it 'registers and corrects an offense' do
         expect_offense(<<~RUBY)

Failures:

  1) RuboCop::Cop::FactoryBot::AssociationStyle when EnforcedStyle is :implicit when `association` is called with non-symbol trait registers and corrects an offense
     Failure/Error:
       expect_correction(<<~RUBY)
         factory :article do
           user factory: [:user, foo]
         end
       RUBY
     
       expected: "factory :article do\n  user factory: [:user, foo]\nend\n"
            got: "factory :article do\n  user\nend\n"
     
       (compared using ==)
     
       Diff:
       @@ -1,4 +1,4 @@
        factory :article do
       -  user factory: [:user, foo]
       +  user
        end
       
     # ./spec/rubocop/cop/factory_bot/association_style_spec.rb:125:in `block (4 levels) in <top (required)>'