isolating dangerous testing examples

* testing/examples/babel-dangerous.org: To house the dangerous.
* testing/examples/babel.org (an): Removed a trouble maker.

testing/examples/babel-dangerous.org

@@ -0,0 +1,15 @@
+#+Title: dangerous code block examples which should be isolated
+#+OPTIONS: ^:nil
+
+* no default value for vars
+  :PROPERTIES:
+  :ID:       f2df5ba6-75fa-4e6b-8441-65ed84963627
+  :END:
+
+There is no default value assigned to =x= variable. This is not permitted
+anymore.
+
+#+source: carre(x)
+#+begin_src python
+  return x*x
+#+end_src

testing/examples/babel.org

@@ -308,15 +308,3 @@ src_sh{echo 2} blocks on the src_emacs-lisp{"same"} line
 #+results:
 [[file:./cv.cls]]
 
-* no default value for vars
-  :PROPERTIES:
-  :ID:       f2df5ba6-75fa-4e6b-8441-65ed84963627
-  :END:
-
-There is no default value assigned to =x= variable. This is not permitted
-anymore.
-
-#+source: carre(x)
-#+begin_src python
-  return x*x
-#+end_src