add challenge test

spec/basic/step02_if_for_spec.rb

@@ -111,5 +111,42 @@
       log(str) # your answer? =>
     end
   end
+
+  context 'challenge' do
+    # Make list containing "a" from array of stage_array and show it as log by loop. (without select method)
+    # (stage_arrayの配列から "a" が含まれているものだけの配列を作成して、それをループで回してログに表示しましょう。(selectはなしで))
+    it 'test if for making' do
+      # write if-for here
+    end
+  end
+
+  context 'Good Luck' do
+    # Change for statement to Array's each (keep result after fix)
+    # (for文をeachメソッドへの置き換えてみましょう (修正前と修正後で実行結果が同じになるように))
+    it 'test if for refactor for to each' do
+      sea = nil
+      for stage in stage_array do
+        if stage.start_with?('br')
+          next
+        end
+        sea = stage
+        if stage.include?('ga')
+          break
+        end
+      end
+      log(sea) # your answer? =>
+    end
+
+    # Make your original exercise as question style about if-for statement.
+    # (if文for文についてあなたのオリジナルの質問形式のエクササイズを作ってみましょう)
+    #
+    # _/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/
+    # your question here (ここにあなたの質問を):
+    #
+    #_/_/_/_/_/_/_/_/_/_/
+    it 'test if for your exercise' do
+      # write your code here
+    end
+  end
 end