Make no-ast-str.patch conditional on Kivy version.

Only apply no-ast-str.patch for Kivy versions below 3.0, since Kivy 3 no longer needs it.

Author: kengoon

pythonforandroid/recipes/kivy/__init__.py

@@ -43,7 +43,7 @@ class KivyRecipe(PyProjectRecipe):
     patches = [
         ("sdl-gl-swapwindow-nogil.patch", is_kivy_affected_by_deadlock_issue),
         ("use_cython.patch", is_kivy_less_than_3),
-        "no-ast-str.patch"
+        ("no-ast-str.patch", is_kivy_less_than_3),
     ]
 
     @property