Merge pull request #21982 from yui-knk/test_suppress_warning

Suppress warnings of `assigned but unused variable`

activerecord/test/cases/relation/where_test.rb

@@ -304,8 +304,6 @@ def permit!
     end
 
     def test_where_with_unsupported_arguments
-      author = authors(:david)
-
       assert_raises(ArgumentError) { Author.where(42) }
     end
   end