e_exec - after an instance has its exe deleted - set exe to NULL

src/bin/e_exec.c

@@ -773,7 +773,8 @@ _e_exec_cb_exit(void *data __UNUSED__, int type __UNUSED__, void *event)
    inst->ref--;
    _e_exe_instance_watchers_call(inst, E_EXEC_WATCH_STOPPED);
    _e_exec_instance_free(inst);
-
+   inst->exe = NULL;
+   
    return ECORE_CALLBACK_PASS_ON;
 }