update custom intervention syntax

Author: cliffckerr

docs/tutorials/t5.ipynb

@@ -355,7 +355,6 @@
     "\n",
     "    def __init__(self, start_day=None, end_day=None, age_cutoff=70, rel_sus=0.0, *args, **kwargs):\n",
     "        super().__init__(**kwargs) # This line must be included\n",
-    "        self._store_args() # So must this one\n",
     "        self.start_day   = start_day\n",
     "        self.end_day     = end_day\n",
     "        self.age_cutoff  = age_cutoff\n",

examples/t5_custom_intervention.py

@@ -10,7 +10,6 @@ class protect_elderly(cv.Intervention):
 
     def __init__(self, start_day=None, end_day=None, age_cutoff=70, rel_sus=0.0, *args, **kwargs):
         super().__init__(**kwargs) # This line must be included
-        self._store_args() # So must this one
         self.start_day   = start_day
         self.end_day     = end_day
         self.age_cutoff  = age_cutoff