Resolve Lint/CopDirectiveSyntax

```
Offenses:

ruby/testdata/example/lib/example/go_struct.rb:4:18: W: Lint/CopDirectiveSyntax: Malformed directive comment detected. Cop names must be separated by commas. Comment in the directive must start with --.
  class GoStruct # rubocop:disable Lint/EmptyClass Methods are defined in ext/example/go_struct.go
                 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
ruby/testdata/example/test/example/tests_test.rb:174:5: W: Lint/CopDirectiveSyntax: Malformed directive comment detected. Cop names must be separated by commas. Comment in the directive must start with --.
    # rubocop:disable Style/GlobalVars this is test for global variable
    ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
```

Author: sue445

ruby/testdata/example/lib/example/go_struct.rb

@@ -1,6 +1,6 @@
 # frozen_string_literal: true
 
 module Example
-  class GoStruct # rubocop:disable Lint/EmptyClass Methods are defined in ext/example/go_struct.go
+  class GoStruct # rubocop:disable Lint/EmptyClass -- Methods are defined in ext/example/go_struct.go
   end
 end

ruby/testdata/example/test/example/tests_test.rb

@@ -171,7 +171,7 @@ class RbAttrTest < Test::Unit::TestCase
       assert { Example::Tests.protected_instance_methods(false).include?(:nop_rb_define_protected_method) }
     end
 
-    # rubocop:disable Style/GlobalVars this is test for global variable
+    # rubocop:disable Style/GlobalVars -- this is test for global variable
     test ".rb_define_variable" do
       Example::Tests.rb_define_variable("$global_var", 1)
       assert { $global_var == 1 }