fix tests

scripts/addons/cam/async_op.py

@@ -72,6 +72,13 @@ class AsyncOperatorMixin:
             return False
 
     def execute(self, context):
+        if bpy.app.background:
+            # running in background - don't run as modal,
+            # otherwise tests all fail
+            while self.tick(context)==True:
+                pass
+            return {'FINISHED'}
+        else:
             self.timer=context.window_manager.event_timer_add(.001, window=context.window)
             context.window_manager.modal_handler_add(self)
             return {'RUNNING_MODAL'}