Undo behavior of 'budget_duration' with '1mo' option

[22mSqRi]

The budget_duration option allows you to specify '1mo', which was originally implemented as an option to reset the budget on the first of each month.(#4188)

However, the '1mo' option has now been modified to specify a period of one month from the set date(#4196), which is not much different from the 'monthly' (30 days) option that can be specified from the web UI.

I think there is a lot of need to reset the budget on the 1st of every month, so we think the behavior of '1mo' should be changed back to reset the budget on the 1st of every month, or a new option should be created to reset the budget on the 1st of every month.

If there is a need for this work to be done, I am willing to contribute.