Rename 03_Code/test_a01.py to 03_Code/tests/test_a01.py

change directory for tests

Author: diogenisAl

03_Code/test_a01.py renamed to 03_Code/tests/test_a01.py

@@ -10,4 +10,4 @@ def test_01():
 def test_02():
     a = Calculator(5,10)
     """ Check that plus(5,10) = 15 """
-    assert a.plus() == 15
+    assert a.plus() == 15