FIX: don't raise an error on integer usernames

lib/user_name_suggester.rb

@@ -39,7 +39,7 @@ module UserNameSuggester
   end
 
   def self.sanitize_username(name)
-    name = ActiveSupport::Inflector.transliterate(name)
+    name = ActiveSupport::Inflector.transliterate(name.to_s)
     # 1. replace characters that aren't allowed with '_'
     name.gsub!(UsernameValidator::CONFUSING_EXTENSIONS, "_")
     name.gsub!(/[^\w.-]/, "_")

spec/components/user_name_suggester_spec.rb

@@ -18,6 +18,10 @@ describe UserNameSuggester do
       expect(UserNameSuggester.suggest(nil)).to eq(nil)
     end
 
+    it "doesn't raise an error on integer username" do
+      expect(UserNameSuggester.suggest(999)).to eq('999')
+    end
+
     it 'corrects weird characters' do
       expect(UserNameSuggester.suggest("Darth%^Vader")).to eq('Darth_Vader')
     end