Use old zc.recipe.egg.

Experimental change: on some platforms z3c.recipe.scripts generate scripts
which fails to run, even in case of building own python.

software/erp5testnode/software.cfg

@@ -73,7 +73,7 @@ update-command = cd ${:location} && ${git:location}/bin/git pull --quiet
 zc.buildout = 1.5.3-dev-SlapOS-009
 
 [eggs]
-recipe = z3c.recipe.scripts
+recipe = zc.recipe.egg
 # Just so buildout executes [slapos.cookbook-repository] before [eggs], as
 # - [eggs] references [slapos.cookbook-repository]
 # - [instance-recipe] needs [slapos.cookbook-repository] to be finished