Fix a false positive for Rails/DynamicFindBy

[koic]

This PR fixes a false positive for Rails/DynamicFindBy when using dynamic finder with hash.

It prevents the following incorrect auto-correction (syntax error).

 def test_find_by_id_with_hash
   assert_nothing_raised do
-    Post.find_by_id(limit: 1)
+    Post.find_by(id: limit: 1)
   end
 end

 def test_find_by_title_and_id_with_hash
   assert_nothing_raised do
-    Post.find_by_title_and_id("foo", limit: 1)
+    Post.find_by(title: 'foo', id: limit: 1)
   end
 end

Refer rails/rails#25671

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