message: fix: re-add all time grain options to the new chart API
diff: @@ -610,6 +610,10 @@ class ChartDataExtrasSchema(Schema):
  "P1M",
  "P0.25Y",
  "P1Y",
  + "1969-12-28T00:00:00Z/P1W", # Week starting Sunday
  + "1969-12-29T00:00:00Z/P1W", # Week starting Monday
  + "P1W/1970-01-03T00:00:00Z", # Week ending Saturday
  + "P1W/1970-01-04T00:00:00Z", # Week ending Sunday
  ),
  ),
  required=False,
  